Y7 Science Flashcards
(300 cards)
1
Q
When lighting a Bunsen burner, which position should my air hole be in?
A
Closed
1
Q
If my Bunsen burner air hole is closed what kind of flame will I have?
A
Safety flame
2
Q
If my Bunsen burner air hole is open what kind of flame will I have?
A
Roaring
3
Q
If my Bunsen burner air hole is half-open, half-closed what kind of flame will I have?
A
Normal blue
4
Q
For heating solids, which Bunsen burner flame should I use?
A
Roaring
5
Q
For gently heating, which Bunsen burner flame should I use?
A
Normal blue
6
Q
Why should you not heat things using the safety flame?
A
They become sooty (carbon deposits)
7
Q
The variable we change is known as….
A
Independent variable
8
Q
Which axis on a graph is the independent variable normally plotted on?
A
X-axis
9
Q
The variable we measure is known as…
A
Dependent variable
10
Q
What kind of numeric data can only have certain values e.g. shoe size?
A
Discrete data
11
Q
What kind of data is numeric and can have any value within a range e.g. height?
A
Continuous data
12
Q
What kind of data could be a word rather than numeric value?
A
Categoric data
13
Q
True/False - a line of best fit must be a straight line?
A
False - the shape depends on the relationship between variables.
14
Q
True/False - a line of best fit should go from point to point
A
False - the line should be smooth. It should go through as many points as possible. There should be an equal number of points above and below the line.
15
Q
Draw a beaker
A
16
Q
Draw a measuring cylinder
A
17
Q
Draw a tripod
A
18
Q
Draw a test tube
A
19
Q
Draw a filter funnel with filter paper
A
20
Q
Organisms
A
21
Q
Question
A
Answer
22
Q
Put these structures in order from largest to smallest -
* Cell
* Organ
* Tissue
* Organism
* System
A
Organism, System, Organ, Tissue, Cell
23
Q
Which system transports nutrients, oxygen, hormones, waste products?
A
Circulatory
24
What is the purpose of the digestive system?
Breaks down food for absorption.
25
Which two systems are responsible for movement of the body?
Muscular and skeletal
26
What is the function of the endocrine system?
Produce and release hormones
27
Which system is responsible for the production of offspring?
Reproductive
28
What is the purpose of the nervous system?
Control and communication within the body
29
Which system is reposible for the removal of waste products
Excretory
30
What processes are associated with the respiratory system
Inhalation, exhalation, gas exchange
31
Name the 4 types of tissue found in animals
Muscle, connective, nervous, epithelia
32
Which part of a microscope is used to magnify an image?
Lens
33
Onto which part of the microscope do you place your slide?
Stage
34
Which 7 processes are often used to characterise something as living
Movement Respiration Sense Growth Reproduce Excrete Nutrition (MRS GREN)
35
Which feature do all living organisms share?
They are made of cells
36
What is the very thin permeable layer of a cell that controls what enters and leaves the cell?
Cell membrane
37
Which part of the cell contains DNA and controls cellular activities
Nucleus
38
Where do respiration (energy release from food) take place in the cell?
Mitochondria
39
Where do most chemical reactions occur in the cell?
Cytoplasm
40
Which features do you find in a plant cell, but not an animal cell?
Cell wall, vacuole, chloroplasts
41
Draw and label an animal cell
42
Draw and label a plant cell
43
Which part of plant cell is filled with cell sap?
Vacuole
44
What green pigment do chloroplasts contain?
Chlorophyll
45
Particle Theory
46
Question
Answer
47
Which state/s of matter can be compressed?
Gas only
48
Which state/s of matter flow
Liquids and gases
49
Which state/s of matter have a fixed volume?
Solids and liquids
50
Draw the particle model diagram for a solid
51
Draw the particle model diagram for a liquid
52
Draw the particle model diagram for a gas
53
Describe the arrangement of particles in a solid
Regular. Particles are touching
54
Describe the arrangement of particles in a liquid
Random. Particles are touching
55
Describe the arrangement of particles in a gas
Random. Particles are far apart
56
Describe the movement of particles in a solid
Vibrate about a fixed position
57
Describe the movement of particles in a liquid
Move around each other
58
Describe the movement of particles in a gas
Move quickly in all directions
59
Name the changes of state
60
What is the melting point of water?
0 degrees celsius
61
What is the freezing point of water?
0 degrees celsius
62
How do the melting and freezing points of a substance compare?
They are the same
63
What is the boiling point of water?
100 degrees celsius
64
What causes pressure in a gas?
Gas particles colliding with the wall of their container
65
What happens to the pressure of the gas when we increase the temperature?
The pressure increases
66
Forces and speed
67
Question
Answer
68
Name the force between two surfaces sliding over one another, that causes them to heat up and wear away.
Friction
69
Name the force that pulls objects towards the centre of the Earth
Weight
70
Name the force acting against any object that is moving through the Earth’s atmosphere.
Air resistance/drag
71
Name the force pushing upwards on an object flying in the air.
Lift
72
Name the force pushing upwards on an object in a fluid.
Upthrust
73
Which force is a push caused by an engine (e.g. aircraft jet engine)?
Thrust
74
What is the unit of force?
newton, N
75
What instrument can we use to measure force in a lab?
newtonmeter
76
If forces on an object are not balanced what do we have?
A resultant force
77
If there is a resultant force on an object, what will happen?
Object will accelerate or decelerate
78
Describe the motion of the car
Stationary
79
Describe the motion of the car
Accelerating
80
Describe the motion of the car
Decelerating
81
Describe the motion of the car
Moving at constant speed
82
Name the forces acting on the car
Up - normal contact force, Down - weight, forward - friction (look back to your notes if you are unsure why), Back - air resistance/drag
83
What is the unit of weight?
newton, N
84
what is the unit of mass?
kilogram, kg
85
What is the formula that links mass and weight
weight = mass x gravitational field strength
86
What is the Earth's gravitational field strength?
10 N/kg (make sure you get the unit right!)
87
What will happen to my mass if I go to the Moon?
stays the same
88
What will happen to my weight if I go to the Moon?
It will change (decrease - the Moon has a smaller mass and radius that the Earth so the gravitational field strength is lower than on Earth)
89
Describe the forces acting on a floating object
Weight = upthrust. These two forces are balanced. There is no resultant force
90
For an object in a fluid, if weight > upthrust, what will happen?
The object will sink
91
What causes upthrust?
There is a higher pressure at the bottom of the object than the top.
92
List 2 characteristics of a streamlined shape
Rounded front
Slowly tapering tail
Smooth shape with no projections
93
Name two ways to reduce resistive forces
Streamlining
Lubrication (reduces friction between moving parts)
94
How do we calculate speed
speed = distance / time
95
If you know the speed of an object and time taken to travel a certain distance, how can you calculate distance?
distance = speed x time
96
If you know the distance an object travelled and the speed it travelled at, how can you calculate the time it took?
time = distance / speed
97
Describe the motion in different parts of the graph?
98
The image shows a distance-time graph. Describe the motion of the object
It is accelerating (the graph is getting steeper, this means that the speed is increasing)
99
The image shows a distance-time graph. Describe the motion of the object
It is decelerating (the steepness of the graph is decreasing, this means the speed is decreasing)
100
The point a lever rotates about is known as....
Pivot
101
In a lever, the distance between the pivot and where the force is applied is known as...
lever arm
102
If I want to increase the turning effect of a lever, what 2 things could I change?
Increase the force applied
Increase the length of the lever arm (i.e. distance from where the force is applied to the pivot)
103
What is another word for turning effect?
moment
104
What name is given to a type of joint that moves backwards and forwards (e.g. a knee)
Hinge
105
What name is given to a type of joint that allows movement in a circle (e.g. a shoulder)
ball and socket
106
What name is given to a type of joint that allows movement around an axis (e.g. an ankle)
pivot
107
What is a pair of muscles that work in opposition to each other called?
antagonistic pair
108
What happens to the shape of a muscle when it contracts?
It gets shorter and fatter
109
What happens to the shape of a muscle when it relaxes?
It gets longer and thinner
110
What links bone to bone?
Ligament
111
What links bone to muscle?
Tendons
112
Why do we have fluid in our joints
To reduce friction between bones
113
Genetics and Reproduction
114
Question
Answer
115
The differences in characteristics between individuals of the same species is known as....
Variation
116
What type of variation is passed on from parents to offspring, via genes during reproduction
Genetic
117
Variation which is the result of differences in the surroundings, or what an individual does.
Environmental
118
Give three examples of genetic variation
blood group, natural skin colour and natural eye colour, free or attached earlobes (there are more - check your Science booklet for examples)
119
Give three examples of environmental variation
Scars, tattoos, hair length (there are more - check your Science booklet for examples)
120
How do you know blood group is a genetic (inherited) and not environmental characteristic?
You are born with a particular blood group
It cannot change during your life
Your lifestyle does not affect your blood group
121
In which part of the cell is genetic information found?
Nucleus
122
How many pairs of chromosomes do (most) human cells contain
23
123
What are chromosomes made of?
DNA (a long molecule)
124
A short section of DNA that codes for specific features is known as what?
Gene
125
How do we describe the structure of DNA?
Double helix
126
How many versions of each gene do we have?
2
127
What are different versions of the same gene known as?
Alleles
128
A person has genotype Hh - which letter represents the dominant allele and which represents the recessive allele
H - dominant. h - recessive
129
In cats - H represents long hair and h short hair. Cat 1 has genotype Hh, cat 2 also has genotype Hh - what is the chance their offspring will have short hair?
25% - possible combinations are HH (long hair), Hh (long hair), hH (long hair), hh (short hair) - you can use a punnet square to work this out
130
Rosalind Franklin is a famous scientist - what is she best known for?
Her research leading to the discovery of the structure of DNA
131
Name the scientists who won the Nobel prize for the discovery of the structure of DNA
James Watson, Francis Crick and Maurice Wilkins
132
What is 1?
Fallopian tube/oviduct
133
What is the purpose of the fallopian tube?
Transport the egg from the ovary to the uterus
134
What kind of cells are found in the fallopian tube that help the egg move through it?
Ciliated cells/cilia
135
What is 2?
Ovary
136
What is the purpose of the ovary?
Stores and releases egg cells
137
What is 3?
Cervix
138
What is the cervix?
This is a narrow opening between the vagina and uterus
139
What is 4?
Uterus
140
In which part of the female reproductive system does a foetus develop?
Uterus
141
What is 5?
Vagina
142
What is 1?
Scrotum
143
What is 2?
Penis
144
What is 3?
Urethra
145
What fluid/s can be transported in a male urethra?
Urine or semen
146
What fluid/s can be transported in a female urethra?
Urine only
147
What is the purpose of the glands (part 4?)
Add fluid to the sperm to make semen. The fluid provides nutrition for the sperm to give it the energy it requires to swim
148
What is 6?
Sperm duct
149
What is 7?
Testis (2 are called testes)
150
What is the purpose of the testes?
Production of sperm
151
What hormone is produced by the testes?
Testosterone
152
What hormones are produced by the ovaries?
Oestrogen and progesterone
153
Why are the testes outside of the body?
Lower temperature is better for sperm production
154
What is the period of life called between childhood and adulthood
Adolescence
155
What is puberty?
the period during which adolescents reach sexual maturity and become capable of reproduction.
156
What controls the changes that happen during puberty?
Hormones (in males - testosterone, in females - oestrogen and progesterone)
157
Give 3 examples of male changes during puberty
voice breaks, hair grows on face and body, body becomes more muscular, testes start to produce sperm, pubic and underarm hair grows, sexual organs grow and develop
158
Give 3 examples of female changes during puberty
pubic and underarm hair grows, sexual organs grow and develop, voice deepens gradually, hips get wider, breasts develop, menstruation starts
159
The menstrual cycle is approximately how many days long?
28
160
What happens on the first day of the menstrual cycle?
Menstruation (period) starts
161
What is menstruation (a period)?
The lining of the uterus comes away and exits through the vagina as blood.
162
What is ovulation?
When an egg is released by an ovary into the oviduct.
163
Approximately when during the menstrual cycle does ovulation occur?
Middle of the cycle (day 14)
164
What happens to the lining of the uterus if the egg is not fertilised?
It breaks down
165
What happens to the lining of the uterus if the egg is fertilised?
It does not break down
166
What is sexual reproduction?
The process of bringing together the egg and the sperm
167
What is fertilisation?
The process in which the nucleus of a sperm cell joins with the nucleus of an egg cell
168
Describe the journey of the sperm through the male and female reproductive system (list the parts it must pass through)
Testis - sperm duct - male urethra - penis - vagina - cervix - uterus - oviduct
169
Describe 2 sperm adaptations that help it perform its function
Tail - helps them swim to the egg.
Mitochondria - helps give the sperm energy.
Digestive enzymes - help the sperm penetrate the egg cell membrane.
Streamlined shape - help the sperm break down the egg's outer layer.
170
Describe egg adaptations that help it perform its function (fertilisation)
Jelly coating- helps by only letting in one sperm.
Nutrients - act as a food source for the developing foetus.
171
How do non-identical twins occur?
172
How do identical twins occur?
173
What do we call the period of foetel development from conception to birth?
Gestation
174
What is formed when the sperm nucleus fuses with the egg nucleus?
Zygote
175
After cell division, what does a zygote then form?
Embryo
176
After further cell division, what does an embryo become?
Foetus
177
How long is the human gestation period?
40 weeks
178
What are 2 functions of the placenta
Provide nutrients (food and water) to the developing foetus
Provide oxygen to the developing foetus (for respiration)
Waste substance (e.g. carbon dioxide) removal.
179
Where is testosterone produced?
In the testes
180
Acids and Alkalis
181
Question
Answer
182
What does this symbol mean?
Environmental hazard
183
What precaution should you take if a chemical contains this symbol?
Environmental hazard - careful disposal is required. Do not place down the sink.
184
What does this symbol mean?
Toxic
185
If you spill some toxic or corrosive chemicals what should you do?
Clean up immediately and wash hands thoroughly.
186
What does this symbol mean?
Corrosive
187
What does this symbol mean?
Explosive
188
What does this symbol mean?
Irritant
189
What does this symbol mean?
Flammable
190
What precaution should you take with flammable chemicals
Keep away from heat, fire and sparks. No naked flames.
191
What is this symbol?
Oxidiser
192
What is this symbol?
Respiratory irritant
193
True or False - Acids are always corrosive?
False. Acids can be irritants or non-hazardous
194
True or False - Acids are more dangerous than alkalis?
False.
195
When handling irritants what precautions should you take?
Wear safety glasses. Wash spills immediately.
196
What colour do acids turn litmus?
Red
197
What colour do alkalis turn litmus?
Blue
198
What colour do neutral solutions turn litmus?
Purple
199
Is water acid, alkali or neutral?
neutral
200
Give 3 examples of acids found in everyday life.
Fizzy drinks, vinegar, juice, battery acid
201
Give 3 examples of alkalis found in everyday life.
Toothpaste, washing powder, hair dye, drain cleaner, bleach
202
What colour will universal indicator be in acids
Red (strong acids) orange or yellow (weaker acids)
203
What is the pH of a strong acid
0 or 1
204
What is the pH of a neutral solution
7
205
What is the pH of an acid?
<7
206
What is the pH of an alkali?
>7
207
What is the pH of a strong alkali?
14
208
What colour will universal indicator be in alkalis?
Blue or purple
209
What colour will universal indicator be in neutral solutions?
Green
210
What colour is red cabbage indicator in neutral solutions?
Purple
211
What colour is red cabbage indicator in acids?
Red or pink
212
What colour is red cabbage indicator in alkaline solutions?
Green
213
Which element do all acids contain?
Hydrogen
214
What contains hydroxide ions?
Alkaline solutions
215
What reaction occurs if we add an acid to an alkali?
Neutralisation
216
When naming salts, sulfuric acid will form a....?
________ sulfate
(the blank space would be the metal from the alkali e.g. copper sulfate)
217
When naming salts, hydrochloric acid will form a....?
__________ chloride
(the blank space would be the metal from the alkali e.g. sodium chloride)
218
When naming salts, phosphoric acid will form a....?
____________ phosphate
(the blank space would be the metal from the alkali e.g. calcium phosphate)
219
When naming salts, nitric acid will form a....?
____________ nitrate
(the blank space would be the metal from the alkali e.g. copper nitrate)
220
When naming salts, ethanoic acid will form a....?
___________ ethanoate
(the blank space would be the metal from the alkali e.g. sodium ethanoate)
221
Sodium hydroxide makes what kind of salts?
Sodium
e.g. sodium chloride
222
Potassium hydroxide makes potassium salts
Potassium
e.g. potassium chloride
223
Acid + alkali -> ______ + ______
Salt + water
224
What is a base?
Any substance that neutralises an acid forming salt + water
225
Is an alkali a base?
Yes! It is a soluble base
226
Why are insoluble bases usually preferred to alkalis where neutralisation is required? e.g. indigestion tablets, soil pH adjustment
If too much alkali is added it will dissolve and make an alkaline solution. If too much insoluble base is added, the substance remains neutral because it does not dissolve.
227
Give some typical properties of metals
Strong, high melting point, good conductor of heat and electricity, shiny when polished.
228
metal + acid ->
Salt + Hydrogen
(remember MASH!)
229
How do we test for hydrogen?
Squeaky pop with a lit splint
230
How do we test for carbon dioxide?
Turns limewater cloudy
231
How do we test for oxygen?
Relights a glowing splint
232
metal carbonate + acid ->
salt + water + carbon dioxide
233
What do you call a mixture if the solid settles out of the liquid if left to stand still?
Suspension
234
What do you call a cloudy mixture where the solid does not settle out of the liquid if left to stand still?
Colloid
235
What do you can a mixture where the solid is dissolved in a liquid
Solution
236
What is a solution?
A mixture where a solid dissolves into a liquid
237
Which "s" describes something that will dissolve in a liquid
Soluble
238
Which word describes something that won't dissolve in a liquid
Insoluble
239
When a solution contains the maximum amount of liquid that will dissolve in it, this is known as
Saturated
240
What is solubility?
The amount of a substance that will dissolve in a given amount of liquid
241
What do you call the substance that will dissolve in a liquid to make a solution
Solute
242
What do you call a liquid into which other substances will dissolve
Solvent
243
When a substance is dissolved in a liquid what happens to the overall mass?
Stays the same. Nothing "disappears" - you have the same number of atoms before and after.
244
What happens to solubility as temperature increases?
It increases
245
Energy and our planet
246
Question
Answer
247
List the 8 energy stores
Chemical, kinetic, gravitational potential, elastic potential, thermal, nuclear, electrostatic, magnetic
248
List the 4 energy pathways
Electrical, mechanical, heating, radiation
249
Is an object is stationary and then starts moving, which energy store has increased?
Kinetic
250
If I raise an object into the air, which energy store has increased?
Gravitational potential
251
What is the unit of power?
watt, W
252
How do you calculate power?
power = energy/time
253
How many watts in a kilowatt?
1000
254
In fuel bills, energy is given in kWh - what is this unit?
kilowatt hours
255
Name 3 non-renewable energy resources
Coal, oil, gas, nuclear
256
Name 3 renewable energy resources
Wind, hydroelectric, solar, wave, geothermal, tidal, biomass
257
Name 3 fossil fuels
Coal, oil, gas
258
How were fossil fuels formed?
Formed from the remains of plants and animals: coal was formed from dead trees and plants; while oil and gas were formed from the remains of marine life that died millions of years ago. As they were buried deeper and deeper enormous pressure and heat turned them into coal/oil/gas
259
What is released when fossil fuels are burnt
carbon dioxide (and other greenhouse gases)
260
Increasing the number of fossil fuels in the atmosphere increases what effect?
The greenhouse effect
261
What fuel is typically used in nuclear power stations?
uranium
262
As the Earth's temperature increases due to an increase in the greenhouse effect, this can lead to...?
climate change
263
Some fuel is burnt to heat water. Describe the energy transfer that takes place. Use the word “store†and “pathwayâ€
The chemical store of the fuel is transferred to the thermal store of the water via the heating pathway.
264
Water in a reservoir falls and drives a turbine which spins. What is wrong with the following description of the energy transfer:
Gravitational potential store to kinetic store
You need to specify the object the store is associated with e.g. the gravitational store of the water is transferred to the kinetic store of the water as it falls, which is transferred to the kinetic store of the turbine.
265
How do you calculate energy efficiency?
Efficiency = 100 x useful output/total input
266
What is the golden rule of energy transfers?
Energy cannot be created or destroyed. Energy in = energy out.
267
When will heat transfer occur?
When there is a temperature difference between two objects
268
What is the difference between temperature and the thermal store?
The thermal store also takes into account the mass of the substance
269
How do particles move in a warmer substance?
Faster (remember temperature is a measure of the average kinetic energy of the particles)
270
Why are solids the best conductors?
Particles are closely packed and regularly arranged allowing vibrations to pass from one particle to another easily.
271
Why are metals good conductors?
They contain free electrons which can gain energy and travel throughout the material.
272
What are the three types of heat transfer?
Conduction, convection, radiation
273
What states of matter can convection occur in?
Liquids and gases
274
As you heat a liquid or gas, what happens to the kinetic store of the particles?
Increases
275
As you heat a liquid or gas, what happens to the spaces between the particles ?
Increases
276
As you heat a liquid or gas, the heated part becomes _________ dense?
Less
277
What is wrong with the following statement - "as you heat a substance, the speed of movement of the particles increases and they expand"
The particles do not expand. The space between the particles expands.
278
Where do convection currents occur in real life? Give 2 examples
Near radiators, in kettles or fluid in a pan on the stove, in the atmosphere, within the Earth's core, hot air balloons...
279
What is the main difference between radiation and conduction and convection?
Conduction and convection rely on particles.
280
What kind of wave is infrared radiation?
Transverse
281
If we increase the temperature of an object, what happens to the infrared radiation it emits?
It increases
282
Which surfaces are the best emitters and absorbers of radiation?
matt black
283
Which surfaces are the worst emitters and absorbers of radiation?
Shiny white or silver
284
Why do we use insulators?
To reduce unwanted energy transfers by heating
285
List 3 features in a home that can reduce unwanted energy transfers?
Draft excluders, double glazing, carpets, curtains, cavity wall insulation, loft insulation, radiator reflectors, fireplace chimney balloons
286
What are the main chemical elements found in plastic?
Carbon and hydrogen
287
In a plastic, short chain m__________ are made into long chain p__________. The process is known as _________________________.
monomer, polymer, polymerisation
288
Which element (beginning with C ) is the fundamental building block of life?
Carbon
289
Name a process that removes carbon dioxide from the atmosphere?
Photosynthesis, dissolving atmospheric CO2 into seawater
290
Name 2 processes that add carbon dioxide to the atmosphere?
Weathering of limestone, combustion of hydrocarbons, respiration from animals and plants
291
When carbon dioxide dissolves in water, what happens to the pH?
It decreases - the water becomes more acidic.
292
By which process does carbon dioxide enter a plant?
Photosynthesis
293
Which gas makes up 78% of our atmosphere?
Nitrogen
294
Approximately how much oxygen is there in the air we breathe?
0.21
295
Which layer of the Earth's atmosphere do we live in?
Troposphere
296
What happens to the atmosphere as you gain altitude?
It becomes less dense
297
The Sun's energy reaches the Earth and is a_______________by the surface. The energy is emitted as i______________ (heat) radiation
absorbed. Infrared
298
Give two examples of greenhouse gases
water vapour, carbon dioxide, methane and nitrous oxide
299
What do greenhouse gases do?
Absorb infrared radiation emitted by the Earth's surface. This causes the temperature of the atmosphere to increase.
