Science Finals D: Flashcards
(472 cards)
1
Q
what does WHMIS stand for ?
A
Workplace Hazardous Material Information .
2
Q
What are the 5 characteristics of living things ?
A
- Living things respond to their environment
- Living things need energy
- Living things grow
- Living things reproduce
- Living things must get ride of waste
3
Q
Electron micrographics
A
Images from electron microscopes
4
Q
Scanning electron microscope ( SEM )
A
Used to see small details like bacteria
5
Q
Who was one of the first to build a microscope ?
A
Leeuwenhoek
6
Q
How much could one of Leeuwenhoek’s microscope magnify ?
A
250X
7
Q
What are the nine pieces of a microscope ?
A
- Eye piece
- Revolving nosepiece
- Arm
- Objective lenses
- Stage
- Light source
- Coarse focus knob
- Fine focus knob
- Base
8
Q
🎆 eyepiece
A
Used for viewing and contains a lens that magnifies
9
Q
🎆 arm
A
Supports the eyepiece
10
Q
🎆 coarse focus knob
A
Brings an object into focus at low or medium power
11
Q
🎆 fine focus knob
A
Brings an object into focus at high power
12
Q
🎆 Objective lenses
A
Magnify the image . 3 or 4
13
Q
🎆 revolving nosepiece
A
Holds the three objective lenses
14
Q
🎆 stage
A
Supports the slide . Stage clips .
15
Q
Light source
A
Supplies the light needed to view the slide
16
Q
🎆 base
A
Supports the entire microscope
17
Q
How do you determine magnification power ?
A
Objective lens x eye piece lens
Example
Low power
4x 10 = 40 magnification power
18
Q
What happens when you look into a compound light microscope ?
A
Inverted and reversed
19
Q
Resolving power
A
The ability to distinguish between two dots or objects that are very close together .
20
Q
What is the resolving power of a compound light microscope ?
A
0.2 microns ( um)
21
Q
What is a wet mount slide ?
What is the point of this ?
A
Place a bit of water on a slide . Add water to the corner or put your object on to the water . Carefully add a plastic over .
This keeps the lenses from getting dirty
22
Q
Names of cell organelles ?
A
Membranes, mitochondria ,Golgi body , cytoplasm, ribosomes , endoplasmic recticulum, cell wall , vesicles , chloroplast , nucleus
23
Q
Organelle
A
Organelle is a cell structure in which functions are carried out to ensure the cell’s survival
24
Q
Cell membrane
A
The protection dome is a protective barrier that controls the flow of materials in and out of the colony .
Surrounds organelles
25
Cytoplasm
Jelly like substance
Liquid atmosphere inside .
Fills in the organelle
26
Nucleus
Organelle that controls all the activities within a cell
27
What does the nucleus contain ?
Deoxyribonucleic acid or DNA
28
DNA
Carries the heredity material that is passed on from generation to generation
29
Mitochondria
Energy producers in the cell . Carries out cellular respiration to produce energy for the cell
30
Cellular respiration
Occurs when the chemical energy we take in food we eat is changed into energy that our cells use to Cary out their activities
31
Metabolism
The total of all the chemical reactions that take place in our cells
32
What is the main difference between plant and animal cells ?
Animal cells do not have a cell wall or a chloroplast
33
Ribosomes
Assembles proteins like a small factory that manufactures proteins
34
Endoplasmic reticulum
Ribosomes are usually attached .
Network of membrane- covered channels that look a bit like folds of a fan . Transfers protein
35
Golgi body
Sorts proteins and packs them into membrane-wrapped structures called vesicles
36
Vesicles
Function like a mail system . Carries proteins, nutrients and water around the cell
37
Vacuoles
Temporary storage compartments that sometimes store waste
38
Lysosomes
When organelles wear out, they are broken down and recycled called lysosomes .
Contains digestive chemicals that break down food particles, crew wastes , and worn-out cell parts .
39
Cell wall
Tough structure that surrounds the cell membrane
Provides protection
40
Chloroplasts
Trap energy from the sun and change it into chemical energy
41
Cell theory
- the cell is the basic unit of life
- all organisms are composed of one or more cells
- all cells come from other living cells
42
Who was Robert Hooke ?
In 1665 , observed that living things contain " cells "
43
Prokaryotic cells
Type of cell whose organelles are not surrounded by membranes
44
Eukaryotic cells
Type of cell whose organelles are surrounded by membranes .
45
Bacteria
Bacteria are prokaryotic cells
46
How do viruses reproduce ?
Viruses are not alive . They carry information ( DNA ) necessary to reproduce it self . Tricks the host cell into making new virus particles
47
Diffusion
Movement of particles from an area of higher concentration to an area of lower concentration
48
Concentration
refers to the amount of substance in a given space
49
Selectively permeable membranes
It allows some materials to pass through it but keeps other materials out .
50
Equilibrium
Equal number of particles on both sides . Particles will move back and forth but the number of particles on both sides continue to stay the same .
51
Osmosis
Osmosis is the diffusion of water particles through a selectively permeable membrane
Water particles move from an area of higher concentration to lower concentration
52
Three examples of osmosis
1) water particles move in and out of the cell at the same rate ( cell retains its normal shape )
2) water particles move in and out of the cell by osmosis ( cell swells )
3) water particles leave the cell by osmosis ( cell shrinks )
53
Reverse osmosis
Water flows from an area of low concentration to an area of higher concentration across a selectively permeable membrane .
Flow only happens when the pressure on lower concentration side of the membrane is increased .
54
What are 3 basic characteristics of systems ?
1. a system is made of individual parts that work together as a whole
2. A system is usually connected to one or more systems
3. If one part of a system is missing or damaged, the system will function well or may not function at all
55
What is an organ system and why are tissues important to them ?
Each body system is called an organ system . Groups of tissue form organs .
Example : heart cells work together to form heart tissue
56
Muscle tissue
Assists in body movement
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Nerve tissue
Transfers signals in the body and its organs to tell the body how to respond to changes in its internal and external environments
58
Connective tissue
Connective tissue holds together and supports other tissues .
Also protects and insulates organs
59
Epithelial tissue
Covers the surface of organs and the body . Lines the inside of mouth, esophagus and stomach .
60
Circulatory system
Transports blood, nutrients , gases and wastes
61
Digestive system
Takes in food, breaks down food , absorbs nutrients, eliminates solid waste
62
Respiratory system
Controls breathing . Exchanges gases in lungs and tissues .
63
Excretory system
Removes liquid and gas wastes from the body
64
Immune system
Defends body against infections
65
Endocrine system
Manufactured and release hormones
66
Reproductive system
Includes reproductive organs for producing offspring
67
Integumentary System
Includes skin, hair and nails . Waterproof protective barrier around the body.
68
Skeletal System
Supports,protects and works with muscles to move parts of the body .
69
Muscular system
Has muscles that work with the bones to move of the body .
70
Nervous
Detects changes in the environment and signals these changes to the body , which carries out a response
71
Four food groups ?
Grain products, vegetables and fruit, milk products, meat and alternatives
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Food pyramid
The width of each band tells you how much you should eat from that group . Wide part of the band means you should choose foods from that group.
Chooses food in moderation .
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Types of nutrients
Carbohydrates , proteins and fats
74
Carbohydrates
Carbohydrates are the body's quickest spice of energy . Two types of carbohydrates : simple and complex.
75
Complex carbohydrates
A chain of simple carbohydrates . Your body needs to break it down into simple carbohydrates before you can use it as energy.
Better than eating a diet high in simple sugars .
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Proteins
Proteins are used to build parts of your body's muscles, skin, hair, and nails .
Fish, poultry, nuts, soy and dairy products
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Fats
Fats are used to build cell membranes and can be stored by the body for future energy uses .
Shortening, butter, oil, cream and meat contain fat.
78
Unsaturated fat
Good fat comes from fruits, vegetables and fish. Vegetable oil, corn oil, olive oil.
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Saturated fats
Solid at room temperature
80
Plaque
Plaque is a fatty mat rial that is deposited along the walls of blood vessels . As plaque builds up in the blood vessels, the flow of blood through heart and body is reduced .
Increased risks heart attacks and strokes
81
Minerals and vitamins
Both needed in small amounts to help your body perform various functions . Such as building bone strength
82
Function and sources of fluorine
Function : Dental cavity reduction
| Source : Fluoridated water
83
Function and source of Iron
Function : formation of red blood cell parts ; transpiration of oxygen throughout the body
Source : liver, eggs, yolks, grains, meats, leafy veggies
84
Function and sources of sodium
Function : nerve activity
| Source : bacon, butter, table salt, veggies
85
Function and source of magnesium
Function : muscle and nerve activity; bone formation
Source : fruits, vegetables, grains
86
Function and source of calcium
Function : teeth and bone formation ;
Muscle and nerve activity
Source: Milk, grains, calcium-fortified Orange juice and soy milk.
87
Function and source of phosphorus
Function : teeth and bone formation ; muscle and nerve activity
Source : milk, grains, vegetables
88
Functions and source of copper ?
Function : development of red blood cells
Source : grains, liver
89
Functions and sources of potassium
Function : muscle and nerve activity
Source : vegetables , bananas
90
Function and source of sulfur
Function : hair, nails and skin builder
Source : grains, fruits, eggs, cheese
91
Diseases when there is a lack of a vitamin
Osteoporosis ( lack of calcium ) : weaken bones .
Rickets ( lack of vitamin D ) : bones to weaken
92
Four stages of digestion .
Ingesting , digesting , absorbing and eliminating
93
Ingesting
Eat the food .
94
Digesting .
Mechanical digestion occurs when you use your teeth and tongue to chew food. Saliva helps breakdown the complex carbohydrates .
95
Mechanical digestion
Occurs when you use your teeth and tongue to chew food
96
Bolus
Small piece of food
97
Chemical digestion
Occurs when amylase begins to break down the food blogs by breaking down complex carbohydrates into simple carbohydrates
98
Food from mouth --> esophagus
Food passes through the pharynx . And when we swallow the epiglottis cover the airway tube . Goes down the esophagus by a process called peristalsis
99
Pharynx
The pharynx is where your airway passage and the rest of your digestive system meet .
100
Epiglottis
A small flap of flesh covers the airway tube when you swallow.
101
Esophagus
The esophagus is the part of the digestive tube that connects the pharynx and stomach .
102
Peristalsis
The process of when the esophagus pushes down the bolts
103
Food in stomach .
Contains gastric juice that breaks down bolus. The bolus turns into a liquid called chyme . Takes 2-6 hours .
104
What is the stomach lined with ?
Mucus ( protects the tissue from being damaged by the acid )
105
What is one of the reasons the gastric juice must be acidic ?
The enzyme Pepsi ( breaks down protein ) needs an acidic environment to function.
106
Gastric juice
Made from hydrochloride acid .
107
What are sphincters and what are their functions ?
Round muscles that open to allow materials to move through them .
108
Food in Small intestine
Absorption of nutrients
109
Duodenum
First meter of small intestine.
110
Pancreas
Produces digestive enzymes that pass into the small intestine .
Enzymes help breakdown carbohydrates, proteins and fat in the chyme .
111
Villi
Villi are structures that look like folds in the wall of the small intestine .
112
Food in Large intestine
Take undigested material from the small intestine and reabsorb the water and some minerals
113
Feces
Solid waste products of the digestion process . Stored in rectum until they are eliminated through Anus.
114
Process of excretion
Removes the liquid wastes trough the unitary tract
115
What are two main organs involved in excretion ?
Two kidneys , two tubes that carry urine ( ureters , bladder , urethra )
116
Kidneys
Filter blood and remove any wastes
117
State two eating disorders and how they can damage the body .
Anorexia nervosa : severely restricts what she or he eats .
Results : medical problems could include damage to internal organs and weakening of bones
Bulimia nervosa : when a person eats a large amount of food and then vomits or takes laxatives to get rid if of food before it can be completely digested
Result : irrational and tooth decay from stomach acid in vomit .
118
4 major chambers in the heart
Right atrium , left atrium , right ventricle , left ventricle
119
Left ventricle
Pumps your blood out to your body
120
Right ventricle
Pumps blood to your lungs
121
Right atrium
Receives blood from body
122
Left atrium
Receives blood from lungs
123
Atria
Allow the blood to move from the body into the heart
124
Ventricles
Pump the blood out of the heart
125
Valves
Each valve allows blood to flow in only one direction
126
Blood vessels
Roads that make up the circulatory system
127
Arteries
Arteries are blood vessels that carry blood away from your heart . Carry oxygenated blood .
Thick walled so it can withstand pressurized flow .
128
Aorta
Largest artery in your body . Width about 25 mm
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Arterioles
Smallest arteries
| Diameter of about 0.5 mm
130
Capillaries
Network of tiny blood vessels that act like a highway interchange . Oxygen, nutrients and glucose diffuse through the very thin walls of capillaries into fluid that surrounds tissue . In exchange of carbon dioxide that diffuse out .
131
Veins
Bring back deoxygenated blood ( thicker than oxygenated blood ) to the heart . Thinner walls because it's not under pressure . ---> superior vena cava and inferior vena cava
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5 types of blood vessels
Arteries , capillaries , veins , aorta , aterioles
133
Plasma
A clear, yellowish fluid that contains numerous proteins, minerals and other substances .
55% of blood
134
Red blood cells
Carry oxygen from lungs to the cells of your body and carbon dioxide from your body cells to your lungs .
Produced in the liver and spleen
135
White blood cells
Fight infection and prevent growth of cancer . Larger than red blood cells . Increases when you are infected .
136
Platelets
Important for clotting blood . Seal the wound by thickening the blood so a scab can form over the cut .
137
What makes the other 45% of blood ?
Red blood cells , white blood cells , platelets .
138
What are the 10 structures you will find in the human respiratory system ?
Nasal cavity , epiglottis , larynx, esophagus, trachea, bronchus, right lung , bronchiole, left lung , pharynx
139
Cilia
Tiny hairs that trap dirt and other particles back out the nostril or down into the digestive system
140
Larynx
Contains your vocal chords
141
Trachea I
Air way passage
142
Bronchi
Base of trachea . Two tubes .
143
Bronchioles
Smaller air tubes
144
Alveoli
Gas exchange . Thin- walled sacs . End of bronchioles
145
Path of air ?
Nose --> cilia --> larynx --> trachea --> bronchi--> bronchioles --> alveoli
146
Gas exchange
Carbon dioxide diffuses into the alveolus and oxygen diffuses the other way into the capillaries and bonds with red blood cells .
Oxygenated blood returns to the heart to be pumped to the rest of the body .
Occurs when the alveoli, capillaries and blood vessels meet .
147
Why is smoking dangerous ?
Destroys the cilia lining in your respiratory system so that dirt and other particles trapped in the mucus cannot be removed easily .
Linked to heart disease and cancer
Many chemicals
148
What are four ways to transmit infectious diseases ?
Direct contact : shaking hands
Indirect contact : being near an infected person who sneezes without covering his or her mouth
Water and food : eating food such as egg that cotnians salmonella
Animal bites : being bitten by an animal carrying the rabies virus
149
Pathogens
Germs . Disease- causing invaders
150
Immune system : first line of defence
Skin and links of all internal body systems. Sweat and oil on skin are slightly acidic ( prevents some pathogens from growing on the surface of your body .
Inside the body : acidic gastric juice
151
Immune system : second line of defence
Immune system recognizes the uniform cells that belong to your body . Attacks unknown cells .
152
Innate immune response
Responds to invading pathogens quickly and general or non-specific . Flow or fluid to the site of infection . Causes swelling and redness in the area ( inflammation ) increase in white blood cells ( phagocytes )
153
Role of phagocytes
Find the invader cell and swallow it .
154
Acquired immune response
Highly specific attack on a particular pathogen or antigen . Might take weeks to develope the exact response to defeat particular invader . Need both B cells and T cells .
155
Antigen
An antigen is any substance the body cannot recognize, from a virus to a splinter . Non- living particle or substance
156
B cells
Recognize antigens present in the body . They produce specific particles ( antibodies ) to fight them . Attach and destroy both antigens and pathogens .
157
Helper T cells
Re on fixes the presence of an antigen or pathogen and activates B cells
158
Killer T cells
Work independently to directly destroy pathogens or antigens
159
Active immunity
Remembers which antibodies should be used to attacking a pathogen that has infected it before
160
Immunity
Some antibodies remain for future use ( memory B cell )
161
Montagu's observation on vaccine
She conducted an experiment where she put a drop of pus from a patient who had a mild case of small drop .
They healed faster than developing the serious form of disease .
162
Jenner's experiment
Gave an eight year cow pox , after recovering .. Small pox did not infect him
163
Vaccine
a special version of an antigen that gives you immunity against a disease
164
Allergy
An high sensitivity to some substance .
165
Disorders of immune system
Allergies and AIDS ( acquired immunodeficiency syndrome )
166
Allergen
Allergic reaction
167
Histamine
A chemical that your body releases when you have an injury or need to fight invaders
168
Anaphylactic shock
| how to make it better
Result in swelling, breathing difficultly or death . People carry adrenaline auto injector . ( help reduce the effects of an allergic reaction )
169
AIDS
Acquired immunodeficiency syndrome
Caused by HIV ( human immunodeficiency virus ) . HIV is a powerful pathogen that attacks the immune system itself and can destroy it by infecting helper T cells . Unable to activate killer T cells or B cells
170
How is HIV transmitted ?
semen and blood .
171
How to take care of your immune system
- eat balanced diet
- maintain personal hygiene
- keep home clean
- avoid tobacco and other non- prescription drugs
- plenty of rest and exercise
- keep vaccinations up to date
- do not engage in activities that involve sharing body fluids with others
172
Force
Push or pull object
173
Crest
Highest point in a wave
174
Trough
Lowest point in a wave
175
Wavelength
Crest to crest or trough to trough
Measured in metres .
Distance over which the wave repeats
176
Amplitude
Height of wave crest or depth f a wave trough measured from rest position .
Related to the amount of energy carried by the wave .
Larger amplitude : carries more energy
Lower amplitude: less energy
177
Frequency
Number of repetitive motions or oscillations , that occur at a given time .
Measured in hertz ( HZ ) or cycles per second .
Shorter the wavelength - greater frequency
178
Medium
Matter the waves travel through
179
Transverse waves
Matter in the medium moves up and down perpendicular to the direction that the wave travels
180
Compression waves
Matter in the medium moves back and forth along the same direction that the wave travels
181
Wave model of light
Pictures light travelling as a wave .
182
Light
A type of wave that travels through empty space and transfers energy from one place to another
183
Visible light
A wave you can see
184
Refraction
Bending or changing direction of a wave as it passes from one material to another
185
Colors of the rainbow from refraction of the light
Red, orange , yellow, Green, blue, indigo, violet .
186
Newton's discovery about light
Prism was not the source of the colours . The different colours met have been present already in the white light .
He was able to to remove the colours with a few prisms .
187
Reflection
Occurs when a light wave strikes an object and bounces off .
188
Additive primary colours
Red, blue , green
189
What happens when you combine red, blue and green ?
White lite
190
Secondary colours
Cyan, yellow and magenta
191
Electromagnetic radiation
The transmission of energy in form of waves that extend from the longest radio waves to shortest gamma rays .
192
7 different types or radiation in the electromagnetic spectrum
Radio waves , microwaves, infrared waves , visible light, ultraviolet waves, x Rays, gamma rays
193
Radio waves
Type of electromagnetic radiation that have the longest wavelength and lowest energy and frequency compared to all other types
194
MRI
Magnetic resonance imaging . Particles int he bones and soft tissues behave like tiny magnets and can be lined up . Produce radio waves and can mallet the different tissues
195
Microwaves
Shortest wavelength and the highest frequency of all radio waves . Only foods that contain water can be heated by the micro wave .
Also can be transmitted to telecommunications satellites that orbit earth. Strengthen them and re transmit them to a new location .
196
Radar
Shorter wavelength microwaves . Used for tracking the movement of automobiles, aircraft, watercraft, and spacecraft . Used for weather forecasting
197
Infrared waves
Type of electromagnetic radiation that has a longer wavelength and Lower energy and frequency .
Used ; read CD-ROMs . Heat radiation
198
Ultraviolet Waves
Type of electromagnetic radiation that had a shorter wavelength and higher energy and frequency .
Enables your body to make vitamin D . Over exposure can result to sunburns and skin cancers , damage to the surface of eye
Kill bacteria in food, water and medical supplies . Fluorescent powder to study fingerprints
199
X rays
type of electromagnetic radiation that have a much shorter wavelength and higher energy and frequency than ultraviolet
200
Gamma rays
Highest energy and frequency and shortest wavelength Portion . Result from nuclear reactions and are produced by the hottest regions of the universe .
Focused burst of gamma rays are used in radiation therapy to kill cancer cells
201
Transparent
Able to transmit light without being completely absorbed . Allows light to pass through it freely . Only a small amount of light is reflected .
202
Translucent
Most light rays get though but are scattered in all directions
203
Opaque
Prevents any light from passing through
204
Why does a shadow form ?
Blocks the rays of light striking you .
205
Light reflecting on smooth surfaces
Smooth and uniformly
206
Light reflecting on a rough surface
Reflect light randomly
207
Law of reflection
The angle of reflection equals the angle of incidence
208
Incident Ray
Incoming Ray
209
Reflected Ray
Ray that bounces off barrier
210
Normal
Imaginary line that is perpendicular to the boundary between two materials and intersects the point at which the incident reaches the boundary
211
Angle of incidence
Angle formed by incident beam
212
Angle of reflection
Form bed by reflected beam
213
Angle of refraction
Angle of Ray of light emerging from the boundary between two materials
214
What happens when light rays go into water
They slow down and bend toward normal
215
What happens when light rays travel from water to air ?
They bend away from normal and speeds it up .
216
Why does a fish in water look closer than it really is ?
Light rays from the fish bend away from normal as they pass from water to air . Makes the fish seem closer
217
Mirage
Misleading appearance or illusion . Light bends as it travels through different densities of air .
218
How image forms on a plane mirror ?
The light reflects off all the points of the object in all direction . All the rays from the blueberry that strike the mirror reflect . That would make your brain thinks that is behind the mirror .
219
Concave Mirrors
Curves inward . All the rays bounce off and meet at a single point called the focal point . Converging .
220
Convex mirror
Diverging .
1. Objects appear to be smaller than they are
2. More objects can be seen in a in ex mirror than in a plane mirror of the same size .
221
Lens
Curved piece of transparent material
222
Concave lenses
Thinner in the middle and far and the end . The light rays diverge
From any location , image is smaller and upright
223
Convex lenses
Fat in middle . Light rays converge .
More than two focal lengths : smaller, inverted
Between one and two focal lengths ; larger, inverted
Object at focal point : no image
Less than one focal length : larger upright
224
Iris
Coloured circle of muscle surrounding the pupil . Controls the amount of light entering the eye .
225
Pupil
Dark : allows more light to enter
| Bright : contracts the pupil to reduce the amount of light entering the eye .
226
Cornea
Made of cells that transparent enough to let light pass through , yet tough enough to hold the year together
227
Sclera
Opaque tissue surrounding cornea . White region surrounding the iris
228
Retina
Screen at the back of the eye , image is formed .
229
Optic nerves
Convert the light rays into electrical signals that are sent to the brain through a thick nerve .
230
How is an image formed in the retina ?
All the light rays come together at the top of the retina. And all of them enter the eye at the bottom . Image formed by lens is inverted .
Brain interprets the image as being upright .
231
What happens to light rays after they enter the eye through the cornea ?
Cornea refracts incoming light rays so that they converge toward the retina. The cornea provides MOST of the focussing done by your eyes.
Lens does the remain focusing.
232
Blind spot
The are where the optic nerve enters the retina does not have any light-sensing cells .
233
Functions of rod cells ?
- able to absorb almost any colour of light ( green light )
- used for night vision
- very light sensitive
- one type of light-sensitive pigment
- have more pigment than cones, so can detect less light
- slow response to light
- smaller than cone cells
- about 100 million in the human eye
234
Functions of cone cells ?
- detecting colour
- 3 kinds of cone cells : red, blue, green
- bright illumination vision
- not very light sensitive
- less pigment than rids, require more light to detect images
- fast response to light
- larger than rid cells
- about 6 million in the human eye
- mostly found in the centre of the retina
235
How do light rays behave with normal vision ?
Converge at the retina . Light rays are diverging when they enter eye . Muscles in the eye cause the lens to change shape . Clear image
236
How do light rays behave for near-sighted vision ?
Light rays form an image in front of the retina . By the time the light rays actually strike the retina they have begun to spread out ( fuzzy image) .
Concave lens is used to diverge the parallel rays so that image forms farther back .
237
How do light Rays behave in far-sighted vision ?
Light rays from didn't at objects are early parallel and require less refraction to converge them than light from nearby objects .
Light rays from nearby objects are diverging as they enter the eye.
Convex lens is need for the light rays to come into focus exactly on the retina .
238
Astigmatism
A normal cornea is shaped spherically , while an astigmatic eye has an irregularly-shaped cornea .
Focus on more than one point on the retina , blurred vision .
Eye glasses , contact lenses , laser surgery to reshape cornea .
239
List the other types of blindness
Snow blindness : temporary partial or complete blinds chased by over exposure to glare of sunlight .
Night blindness : difficult or impossible to see dim light
Colour blindness : ability to only see shades of grey.
240
What can cause focussing problems as children grow and adults get older ?
shape of their eye changes .
Flexibility of the eye lenses decreases, making it harder focus on nearby objects .
241
How does light travel through a microscope ?
The screen must be place where all the light rays from a given point on the object converge . The image with form where the two light rays meet .
242
Refracting telescopes
Lenses bend the light to focus it .
Both : an objective lens collected light and focussed it into an image .
Problems : in order to see detailed image of distant objects , objective must be large as possible .
243
Reflecting telescopes
Used a concave mirror, plane mirror and convex lens to collect and focus light from distant objects .
Light from a distant objects enters one end of the telescope and strikes a concave mirror at the opposite end . Reflects off this mirror and converges . Before it converges light is reflected from the plane mirror toward the tel scopes eye piece . Converge at the focal point , creating image of the distant object .
Two mirrors
244
Hubble space telescope
Primary mirror 2.4 m across and collect visible light and other electromagnetic radiation from planets, stars and distant galaxies .
Clear and not blurred from earth's atmosphere.
245
Binoculars
Two refracting telescopes mounted side by side . Prisms reflect the light in binoculars back and forth inside a shorter tube .
246
Cameras
Works by gathering and bending light with a convex lens. Lens projects an image onto a light detector to record a digital image of a scene . Shorter opens to allow light to enter the camera . Subject meters the camera through the aperture.
Light passes through the lens which focuses the image on the light detector . Convex lens is used , inverted and smaller than actual object .
247
Wide angle lenses ( camera )
Short focal length produce small image of object but wide field of view .
Need to be close to the light detector to form a sharp image win their short focal length.
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Telephoto lenses
Longer focal lengths. Through a telephoto lens seems enlarged and closer than it actually is .
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What are the similarities that the camera have to the human eye ?
Lens cap = human eyelid
Diaphragm ( number of opaque circles arranged in a circle ) = iris
Light passes through the lens and forms an inverted image in both camera and the eye .
Pixels on the CCD = rod and cones
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How is a camera different from a human eye ?
Changing in the distance between the lens and the detector does the focussing in a camera . 🚫 humans lens changes shape , rather than moving closer to the retina
The CCD detector at the back of the eye is like the retina and the optic nerve . It does not need two functions , one is enough c:
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CCD
Charged-coupled device .
Absorbs light and provides the electrical signals needed to produce a digital image .
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Laser light
Light rays are moving in the same direction and all of the crests and troughs of light are lined up . Does not refract into a rainbow . Only one wavelength .
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Laser surgery
Remove cataracts , re-attach retinas , stop bleeding , reshape corneas
Laser is used to cut through the cornea so that the lens can be replaced with a synthetic one .
Able to seal off blood vessels
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Changing shape of cornea with laser surgery .
Laser to weaken the surface of cornea , allows it to be folded back . Changes shape of inside of the cornea . The outer surface can be returned to its original place .
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Optical fibre
Transparent glass fibers that can transmit light from one place to another .
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Uses for optical fibers
Transmit images of the inside of a person's body from a tiny camera .
Transmit telephone , video and Internet signals
Broadband transmissions
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Total internal reflection
Every time a light Ray strikes the wall of the fibre it is reflected back into it .
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Matter
Anything that has mass and volume
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Mass
Quantity of matter
Grams , kilograms .
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Volume
Amount of space taken up by a substance or object
Measured in :ML , L , CM^3
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Three states of matter
- solid is the state that has a definite shape and volume
- liquid is the state of matter that has a definite volume but it's shape is determined by its surroundings
- gas is the state that has its volume and shape determined by its surroundings
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Kinetic molecular theory
1. All matter is made up of very small particles
2. There are spaces between particles
3. The particles that make up matter are always moving
4. Particles are attracted to one another .
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Kinetic energy
Energy of motion
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Thermal expansion
Material that is made up of particles expands when the temperature increases .
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Thermal contraction
Particles take up less space as they lose energy , decreases in volume .
266
Thermal energy
The total amount of energy of the substance
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Heat
Energy transferred from one material or object to another as a result of a difference in temperature or a change in state .
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Temperature
You are sampling the average kinetic energy of its particles .
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Melting
Solid --> liquid
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Evaporation
Liquid ---> gas
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Condensation
Gas--> liquid
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Solidification
Liquid ---> solid
273
Sublimation
Solid --> gas
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Deposition
Gas --> solid
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Density
Mass of a given volume . Describes how closely packed together the parties are in a material
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Density in liquid ?
Less dense than a solid
277
Density in gas ?
Less dense than liquid
278
Density In solid
Denser than liquid
279
Layers of density in fluids ?
Less dense liquids will float on top of liquids .
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Density of air
Relatively dense close to Earth's surface . Oxygen is more close .
The higher we go , the less oxygen .
Air particles are more spread out .
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Displacement
Amount of space that an object takes up when placed in a fluid .
Fill a container up to a certain height . Place object in water . See how much the water rises .
282
How to calculate density ?
Density = mass divided by volume
283
Contact forces
Tension force , friction force , elastic force .
284
Force
Push or pull that acts on an object .
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Action-at-distance forces
Gravitational force , electrostatic force , magnetic force
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Tension force
Experienced by a wire or a rope when it's pulled at either end
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Friction force
Works to slow down or stop motion due to surfaces rubbing against each other .
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Elastic force
Extorted when a spring like object restores itself to Normal shape after it has been compressed or stretched .
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Gravitational force
The force attraction between objects because they have mass .
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Electrostatic force
Called static electricity , causes pushing and pulling forces .
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Magnetic forces
Acts on certain metals and compounds
292
How is mass measured
Measured in grand , kilograms ,
Use a balance scale to measure mass
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Weight
Amount of force on an object due to gravity .
Weight scale .
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Newton
Measuring unit of force .
295
Force meters
Equipped with a sprig or similar elastic device that stretches or compresses in response to being pulled or pushed .
Newton gauge or spring scale.
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How to convert mass to weight ?
For every kg multiply by 9.8
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Balanced forces
Are equal strength and oppose each other in direction
298
Unbalanced forces
Cause a change in the speed or direction of an object .
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Pressure
Amount of force acting over a given area of an object
300
Compression
Decrease in volume produced by force .
301
Why are gases easily compressible ?
Large amount of space between its particles .
302
Deformation
Change of shape without being forced into smaller volume .
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Why does a can that was heated , contract when it is removed from the heat ?
As it cools , the pressure on the inside is lower then outside . Pressure on the outside pushed the walls of the can inward , crushing the can .
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Why are solids and liquids hard to compress ?
There's not enough space .
305
Formula for pressure
Force divided by area
306
Units for pressure
Pascal 1N/m^2
| 1000 Pa= kilo pascal
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Viscosity
Resistance of a fluid to flow . The slower the fluid the greater the viscosity .
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Flow rate
Speed at which a fluid flows from one point to another .
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Effect of temperature on viscosity ( liquid )
Heated ---> viscosity decreases
| Called ---> viscosity increases
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Effect of temperature on viscosity ( gas )
Heated ---> viscosity increases
| Cooled ---> viscosity decreases
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Adhesion
Attracting or joining of two different objects or fluids to each other .
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Cohesion
refers to the strength with which the particles of an object or fluid attract each other .
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Polarity
One end of each molecule is slightly positive the other side is slightly negative .
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Surface tension
Property of a liquid in which the surface of liquid acts like a thin skin or membrane
315
Atmospheric pressure ( high and low altitudes)
High : air is less compressed .
| Low : less dense
316
What happens when there is a pressure difference between high pressure and low pressure ?
Example juice box .
Creating a lower pressure in your mouth will allow the higher pressure around the juice box to bring the juice in your mouth .
317
Units for atmospheric pressure ?
One atmosphere . 10 metre you descend into the water , pressure increases by one atmosphere .
100,000 N = 1 atm
318
Buoyancy
The tendency of objects in fluids to rise or sink because of density differences with their surroundings .
319
Buoyant force
The upward force exerted by a fluid
320
Convection
Vertical movement of fluids caused by different densities .
321
What happens when the weight of the object is greater than thebuoyant force ?
It sinks
322
Hydraulics
Study of pressure in liquids
323
Hydraulic systems
Devices that create pressure that moves through a liquid such as oil or water .
324
Static pressure
Squeezing an enclosed fluid
325
Dynamic pressure
Energy that can be used directly to perform tasks .
326
Pumps
Used to raise or move fluids .
327
Valves
Device for controlling the passage of fluid through a pipe .
328
Check valves
Valves that allow fluids to flow in only one direction .
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How does water get into your house ?
Pumps force water through a pipe into a pressure tank. As more and more water enters the tank , it pressurizes the small amount of air in the tank. When the appropriate pressure is reached , the pressure tank transmits water under pressure through the entire system .
330
Hydraulic multiplication
Incompressible fluid increases and transmits a force from one point to another.
🎆
🌚 ^^
🌚 ^^
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Problems with hydraulics ?
Twists and turns that would increase resistance to flow . Pipes need to be connected carefully to avoid leakage .
Fluid particles lose energy as they brush past each other . Build up of sludge, corrosion and mineral deposits all interfere with water flow .
332
Pneumatics
Use of gas in an enclosed system under pressure .
333
How can pneumatics work with hydraulics ?
Stopping a heavy truck . The hydraulic multipliers in the wheels increase the force that stops the vehicle . Highly compressed air delivers great force to the braking system .
334
Problems with pneumatic system .
The flow of air could be blocked if it is not cleaned regularly . It creates rising air pressure . There is no longer a strong pressure difference to force the air into .
335
How do living things rely on water and fluid systems ?
- body : absorb food , transport nutrients , remove wastes and protects your tissues , proper blood pressure , proper blood circulation ,
336
Blood pressure
The force of blood on the walls of blood vessels .
337
Sphygmomanometer
Measures blood pressure by applying enough pressure to an artery in your arm to briefly stop the flow of blood .
338
Two values of blood pressure ?
- indicator of your general Heath
| - early warning for diseases
339
Normal blood pressure
120/75 mm
340
High blood pressure
Faster heart beat , increase blood pressure , flow of fluid is reduced or blocked , harden arteries , might make them burst .
341
Low blood pressure
Not enough blood flow , low water levels ,
342
Two methods that make the chest cavity change size for breathing ?
The diaphragm in the lower chest moves downward as you breathe in .
The muscles between the ribs , which move the rib cage up and out .
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Inhaling and exhaling
Exhaling : the chest cavity contracts and the diaphragm muscle moves up and air is pushed out of the lungs
Inhaling : chest cavity expands to create an area of low pressure in the lungs .
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Asthma
Disease of the respiratory system that interferes with the normal flow of air into the lung .
Attack : causes the pathway to the lungs to narrow, making it difficult to breathe .
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Hydrologist
Person who studies Earth's water systems and helps find solutions
346
Oceanographers
People who study ocean systems specially
347
Salinity
Amount of salt dissolved in water
348
What parts of the ocean are more salty then others ?
Close to the equator , high rates of evaporation . North and south poles ( water freezes and salt is left behind )
349
Why are the salinity is usually lower near continents ?
Fresh water rivers empties into the ocean and dilutes the salt water.
350
How do volcanoes contribute to the salt of water ?
Spew material high into the atmosphere . These material fall direct into the ocean or onto earth's surface from where they get carried to the ocean as a run-off .
351
Undersea volcanic eruptions
Release large amounts of sulcus, fluorine, chlorine and hydrogen into ocean water .
352
What are the two main dissolved solids found in ocean water ?
Sodium ions and chloride ions . Sodium chloride .
353
Density
Measure of the mass of an object of a given volume .
354
Why is the freezing point of salt water lower than that of freshwater ?
Ocean water contains far more dissolved salt than fresh water fakes .
-1.9 degree Celsius
355
Does freshwater or salt water have the greater density ?
Saltwater
356
Run-off
Water that flows over the surface of the ground and runs off into streams and rivers, other water bodies and city sewers .
357
What affects how much run-off is created ?
- the nature of the ground material
- the amount of rain
- length of time it rains
- the slope of the land
- the amount of vegetation
- amount of development in the area
358
Drainage basin
The area of land on which precipitation falls and works its way into a common river .
359
Ground water
Water that makes its way into the spaces of of rock .
360
Aquifer
A layer of rock that is porous and allows water to flow through .
361
Reservoir
Large surface storage area . Human made
362
Water table
Lies at a level called the zone of saturation . The depth where water can be found .
363
Glaciers
Freshwater trapped in large masses of snow and ice .
364
What are the two types of glaciers ?
Alphine - glaciers are located in mountain areas
Continental glaciers - ice sheets that cover large areas of land .
365
Crevasses
Deep cracks
366
Ice bergs
Big chunks of icebergs
367
Weathering
Process of breakdown rock into smaller fragments .
368
Physical weathering
Rocks are broken down by physical means
369
Chemical weathering
A chemical reaction chases rocks to breakdown or decompose .
370
Biological weathering
Physical or chemical weathering caused by a plant or animal .
371
Erosion
Weakens and broken down fragments will be transported from their original location .
372
Physical weathering examples
Water in pores and cracks . Could freeze and crack the rock
373
Karst
Area with many sinkholes
374
What is phytoplankton and zoo plankton
Phytoplankton : plants that produce their nutrients through photosynthesis
Zoo plankton : animals that eat other plankton for food
375
What are lakes and ponds used for ?
- Providing a habitat for many plants and animals
| - supporting rooted plants , which clean water through natural processes
376
How do wetlands contribute to the environment ?
- vegetation acts as a filters for removing pollutants from the water
- wetlands hold a huge quantity of water, which helps prevent flooding
- many of the freshwater fish of British Columbia spawn in wetland environments
- a huge variety of wildlife makes wetlands their home
- thick vegetation of wetlands help keep shorelines stable and minimizes erosion
- many endangered species visit wetlands as part of their life cycle
377
Estuary
An area of land that builds up where a river meets the ocean .
378
What makes estuaries ideal environments for both plants and animals ?
Nutrients come from land, rivers, ocean
- water is brackish ( salt and fresh )
- action of tides flushes pollutants and debris out of estuaries
379
Chemical change
Change in matter that occurs when substanc w combine to form new substances
380
Physical change
New appearance but no new substances formed
381
Physical properties
Charade tics of matter that can be observed or measured
382
Malleability
Ability to be beaten into sheets
383
Ductility
Ability to be drawn into wires
384
Solubility
Ability to dissolve in water
385
Conductivity
Ability to conduct electricity or heat
386
Density
Ratio of a material's mass to its volume .
387
Pure substance
A substance that is made up of only one kind of matter
Gold, water, oxygen
388
Element
A pure substance that cannot be broken down or departed into simpler substances
389
Compound
A pure substance composed of at least two elements combined in a specific way .
390
What was John Dalton's (1766-1844) theory ?
- all matter is made of small particles called atoms
- atoms cannot be created, destroyed, or divided into smaller particles
- all atoms of the same element are identical in mass and size, but they are different in mass and size from atoms of other elements
- compounds are created when atoms of different elements link together in definite proportions
391
J.J thomson's theory ? ( 1856-1940 )
- currents were streams of negatively charged particles ( electrons )
- atoms are made up of other particles
- raisin bun model
392
Ernest Rutherford (1871-1937) theory ?
- large space within atoms
- discovered there was a nucleus
- proton and neutron
393
Proton
Positive electric charge
394
Neutron
No electric charge
395
Niels Bohr (1885-1962)
He proposed that electrons surround the nucleus in specific energy levels or shells . More energy --> electrons Jump from low to high energy levels .
396
What charge is the nucleus ?
Positive
397
What subatomic particles are located at the nucleus ?
Proton and neutron
398
Metals
Typically hard, shiny, malleable, ductile and good conductors of heat and electricity
399
Hydrogen
Colorless , odorless, tasteless, highly flammable .
Lightest element
400
Iron
Strong metal . Can be mixed carbon to make steel .
Ductile, heated and drawn into a wire .
Can rust when exposed to water and oxygen
401
Oxygen
Non-metal
Oxygen and sugar to release energy
React with lots of elements
Very reactive
402
Sodium
Metal
Soft
Very reactive
403
Chlorine
Pale yellow-green gas . Added to water in swimming pools to kill bacteria .
404
Mercury
Liquid at room temperature.
| Excellent conductor of electricity poison
405
Sliver
```
Metallic
Malleable
Ductile
Conductor of heat and electricity
Reflectivity
Thermal conductivity
```
406
Silicon
Metal lustre
Semiconductor
Good conductor at high temperatures
407
Alkali metals
Highly reactive
Reactivity increases as you go down the group
Reacts with both oxygen and water
Low melting points ( lower than 200 degree Celsius)
408
Alkaline earth metals
Less reactive than the alkali metals but will burn if heated .
- produce bright flames
- react with water
409
Halogens
Non metals
| Highly reactive
410
Noble gases
- Most stable and unreactive elements
| - colorless and odorless gases
411
Valence electrons
Electrons on the other most shell
412
Valence shell
Outermost shell
413
Covalent compounds
Atoms combine by Sharing electrons to form molecules
414
Molecule
Group of atoms in which the atoms are bound together by sharing one or more pairs of electrons
415
Ionic compounds
Atoms gain or lose electrons to form ions .
416
Ionic lattice
A repeating pattern of positive and negative ions .
417
Polyatomic ion
Gain or lose one or more electrons as their atoms Combine to form a molecule .
418
What polyatomic ion is used to test if drivers had alcohol ?
Dichromate Cr2O72-
419
What are uses for ammonium ?
Fertilizer
420
Reactants
Substances that are going to react
421
Products
New substances that are produced from reactants
422
Evidence that a chemical change occurred
- colour change
- heat, light, sound produced ( consumed )
- bubbles of gas form
- a precipitate may form
Example ; ripe Apple rots
423
Exothermic
The overall release of energy in the form of heat and light .
424
Endothermic
Absorption of energy by the system
425
Celestial bodies
General term for all objects in the sky , sun, moon , planets
426
Hubble's propsal
Galaxy was expanding in all directions . As the universe expands , galaxies spreads apart .
427
What was the Big Bang theory ?
The theory that approximately 13.7 billion years ago an unimaginably tiny volume of space suddenly and rapidly expanded to immense size .
428
Supporting info about the big band theory ?
Penzias and Wilson kept receiving background noises which that now call cosmic background . Radiation left from the Big Bang theory .
Cosmic background explorer . Scientists created a COBE map of cosmic background radiation in the universe . Radiation believe is left over from the Big Bang theory
429
Nebula
A cloud of gas and dust
430
Spiral galaxy
Looks like a pinwheel from above .
Looks like a paper plate from edge
Glow surrounded is called halo
431
Elliptical Galaxy
One that ranges in shape from a perfect sphere to a stretched out ellipse .
Galaxies contain some of the oldest stars
Largest galaxies are elliptical
432
Irregular
Does not have any regular show such as spiral arms or an obvious central bulge
Made up of newly forming stars and old stars .
433
Globular cluster
Composed of as many as 1 million stars , held together by mutual gravity in a spherical shape
434
Open Cluster
Contain few hundreds to a few tens of thousand stars
435
Proto star
Early phase of star
436
How does a star form
A star begins to form from the materials in a nebula when gravity starts acting on chunks of gas and dust .pulling them together .
437
Nuclear fusion
Hydrogen atoms combine with heavier Element helium
438
Low mass stars
Small , dim , cool red dwarfs burn hydrogen slowly . White dwarfs quietly burn out .
439
Intermediate mass stars
```
Similar mass to sun
Burn hydrogen faster
Long time --> red giant
Red giant ---> white dwarf
White dwarf ----> black drawf
```
440
High mass stars
Average life is 7 billion years .
| Supernova --> decompose and provide nutrients for other things to grow
441
Black holes
After exploding from a supernova it becomes a black hole . The material is so dense it has a huge amount of gravitational force . Nothing can escape their pull .
442
Hertz sprung- Russell diagram
Diagram of different stars
443
What is the temperature of the dim stars ?
Hot
444
Temperature of supergiants ?
In the middle
445
Doppler effect
The change in wavelength because of motion . For an observer moving relative to its source
446
Interstellar matter
Made up of gas
447
Red shift
Light source moves away from the person .
448
Solar wind
High energy particles rush past earth . Generate large geomagnetic storms
449
Solar prominences
Large loops of super hot gas that extend out from the sun's surface
450
Solar flare
Violent eruptions of gas
451
Sunspots
Dark patches . Slightly cooler parts of the sun .
452
Corona
Outermost of the sun's atmosphere
453
Photosphere
Hot gases rise to the surface, cools and sinks back into deep layers .
454
AU
Astronomical unit
| About 150 million in = 1 AU
455
Asteroids
Small bodies that are believed to be leftover remains of the formation of the solar system . Orbit the sun in a band between Mars and Jupiter .
456
Comets
Composed of ice, rock , gas
Hurtle through a space originating from Kuiper belt and Oort Cloud .
When affected by sunlight --> gas and dust steaming behind it .
457
Why are objects that circle the sun beyond the orbit of Neptune ?
Trans-Neptunian objects
458
Kuiper belt
Flat disk of millions of small bodies . Composed of fragments of material left over from formation of the solar system .
459
Oort Cloud
Farthest reaches of sun's gravitational influence . Cloud of icy fragments of debris .
460
Light years
Measured the distance that light travels in a year . 300,000km/s equal to 9.5 trillion .
461
How to use triangulation ?
Measure straight baseline
| Measure angles to a point on the distant object . Make a scale drawing .
462
Parallax
The apparent shift of your thumb against the stationary ( un moving ) background .
463
Phases
Changing appearance of the moon
464
What is the clearest evidence that earth is affected by moon's gravitational force ?
The ocean level rises in some area and at some areas , the tide falls .
465
Solar eclipse
Moon shadow on earth .
466
Lunar eclipse
Earth's shadow on the moon .
467
Constellations
Groups of stars that form distinctive patterns
468
Meteoroids
Pieces of rock floating through space
469
Satellites
Electronic devices put in orbit around earth to relay information . Orbits another body in space
470
Geosynchronous orbit
Orbit earth at the same rate that earth is rotating . Satellite seems to be staying in the same position
471
Probes
A space vehicle to other celestial bodies . Designed to travel millions of kilometres . Do not need a crew
472
Terraforming
Process of taking a piece of trash and making it live able to humans .
