Topic 2- Organisation Flashcards
(254 cards)
1
Q
What are large multicellular organisms made up of?
A
organ systems
2
Q
what is the process where cells become specialised for a particular job called?
A
differentiation
3
Q
when does differentiation occur?
A
during the development of multicellular organism
4
Q
what do specialised cells form?
A
tissues
5
Q
what is a tissue?
A
a group of similar cells the work together to carry out a particular function
6
Q
Name three examples of tissues
A
Muscular tissue, Glandular tissue and Epithelial tissue.
7
Q
What is the function of muscular tissue?
A
to contract to move whatever its attached to.
8
Q
what is the function of Glandular tissue?
A
to make and secrete chemicals like enzymes and hormones.
9
Q
what is the function of epithelial tissue?
A
to cover parts of the body.
10
Q
give an example of parts of the body epithelial tissues cover
A
inside of the gut
11
Q
what are tissues organised into?
A
organs
12
Q
What are organs?
A
a group of tissues that work together to perform a certain function.
13
Q
what three tissues is the stomach made up of?
A
Muscular tissue, Glandular tissue and epithelial tissue.
14
Q
What is the function of Muscular tissue in the stomach?
A
moves the stomach wall to churn up food.
15
Q
what is the function of glandular tissue in the stomach?
A
makes digestive juices to digest food.
16
Q
what is the function of epithelial tissue in the stomach?
A
covers the outside and inside of the stomach.
17
Q
How big is an epithelial cell?
A
less the 0.1 mm
18
Q
How big is the stomach?
A
about ten cm, over 1000 times longer than an epithelial cell.
19
Q
What are organs organised into?
A
organ systems
20
Q
What is an organ system?
A
a group of organs working together to perform a particular function.
21
Q
What does the digestive system do?
A
breaks down and absorbs food
22
Q
what is the digestive system made up of?
A
glands , The stomach and small intestine, the liver, the small intestine and the large intestine.
23
Q
What is a role of the glands?
A
e.g the pancreas and salivary glands which produce digestive juices.
24
Q
what is the role of the stomach and small intestine?
A
they digest food
25
what is the role of the liver?
produce bile.
26
What is the role of the large intestine?
absorbs water from undigested food leaving faeces
27
What do organ systems that work together form?
organisms
28
What are enzymes?
biological catalysts produced by living things
29
why do chemical reactions in the body need to be carefully controlled?
to get the right amount of a substance.
30
How can you increase rate of reactions in the body?
raising the temperature.
31
Whats the disadvantages of raising the temperature to get a quicker ROR?
you would speed up the useful reactions but also the unwanted reactions too. also there a limi to how far you can raise body temperature before cells start to become damaged.
32
What do enzymes reduce the need of?
high temperatures. We only have enzymes to increase rates of useful reactions in the body.
33
What are catalysts?
a substance that increases the speed of a reaction with out being changed or used up in the reaction?
34
What are enzymes made up of?
large proteins in unique shapes.
35
What are proteins made up of?
long chains of amino acids.
36
Why do enzymes have special shapes?
so they can catalyse reactions.
37
What do chemical reactions usually involve?
things being split apart or joined together
38
What is the active site on a enzyme?
A unique shape that the substrate fits into.
39
How many reactions can enzymes catalyse?
usually one specific reaction.
40
why do enzymes only catalyse one reaction?
because the substrate has to match the enzymes active site for the reaction to be catalysed.
41
What diagram shows how enzymes work?
'lock and key' model.
42
How does the lock and key model differ from the actual process?
because the model doesn't show 'induced fit' . (the active site actually changes shape slightly as the substrate binds to it for a tighter fit.)
43
What do enzymes need to work efficiently?
the right temperature and pH.
44
What does the temperature effect enzyme?
The higher the temperature the ROR increases. All enzymes have optimum temperatures they work best at.
45
What happens if the enzyme gets too hot?
bonds holding the enzyme together break, this changes the shame of the active site so substrates won't fit anymore. the enzyme is denatured.
46
How does pH affect enzymes?
if the pH is too low or high the pH will interfere with the bonds holding the enzyme together. The shape of the active site changes and the enzyme is denatured.
47
Whats the most common optimum pH for an enzyme?
pH 7 (neutral), but this isn't always the case.
48
give an example of an enzyme that doesn't have an optimum pH of 7.
Pepsin - breaks down proteins in the stomach. It works best at pH 2. this means its more suited for the acidic conditions.
49
How do you carry out a practical that investigates the effect of pH on enzyme activity?
1- drop a spot of iodine solution into every well of a spotting tile.
2-place a bunsen burner on a heatproof mat, place a tripod and gauze onto of the bunsen burner. put a beaker of water onto of tripod and heat the water 35 degrees.
3- use syringe to add 1cmcubed of amylase solution and buffer solution (pH 5) to a boiling tube. using testable holders, put the tube into the beaker . and wait for five minutes.
4- use a different syringe to add 5cmcubed of a starch solution to the boiling tube.
5- immediately mix the contents and start stop clock
6- use a continuous sampling to record how long it takes the amylase to break down the starch. To do this use a dropping pipette to take a fresh sample from the boiling tube every 30 seconds and drop into a well. When the iodine remains browny orange starch is no longer present.
7- repeat the experiment with different buffer solutions of different pH values.
8-contol any variables each time, e.g concentration and volume of amylase.
50
how do you calculate rate of reaction?
rate = 1000/time or change in product formed/time
51
After enzymes breakdown big molecules such as starch, proteins and fats what happens?
the new smaller molecules such as amino acids, glycerol and fatty acids are soluble and can pass easy through the walls of the digestive system. They can then be absorbed into the bloodstream.
52
what converts carbohydrates into simple sugars?
carbohydrases.
53
give an example of a carbohydrase.
amylase (enzyme)
54
give an example of a carbohydrate.
starch.
55
name three places amylase is made.
salivary glands, the pancreas, the small intestine.
56
give an example of sugars.
maltose or dextrins
57
what converts proteins into amino acids.
proteases
58
where are proteases made?
the stomach, the pancreas and the small intestine.
59
what is protease called when its in the stomach?
pepsin
60
what converts lipids into glycerol and fatty acids?
lipase
61
what are lipids?
fats and oils.
62
what two places makes lipase?
the pancreas and the small intestine.
63
What is the purpose of bile?
neutralises the stomach acid and emulsifies fats.
64
Where is bile produced?
in the liver
65
where is bile stored?
Gall bladder
66
What organ is bile releases into?
The small intestine.
67
What is an issue with hydrochloric acid in the stomach?
makes the pH in the stomach acidic for enzymes in the small intestine to work properly.
68
How does bile help enzymes in the small intestine to work properly?
Bile is alkaline so it neutralises the stomach acid and makes conditions alkaline.
69
What conditions do enzymes work best at?
alkaline conditions
70
What does emulsifying fats mean?
Breaking down the fats into smaller droplets.
71
Why are fats emulsified?
it gives fats a greater surface area of fat for lipase to work on, digestion is faster.
72
What is made in the salivary glands?
amylase enzyme in the saliva.
73
What is the Gullet?
Oesophagus.
74
What enzyme does the stomach produce?
protease (pepsin)
75
Why does the stomach make hydrochloric acid?
To kill bacteria,
| To give the right pH for pepsin to work (pH 2 - acidic)
76
What pH does the enzyme pepsin work best at?
pH 2 - acidic
77
What are the muscular walls of the stomach used for?
To pummel food.
78
What is produced in the liver?
Bile.
79
What is the purpose of the gall bladder?
To store bile and release it into the small intestine.
80
What does the pancreas produce?
Protease, lipase and amylase.
81
Where does the pancreas release enzymes to?
The small intestine.
82
What happens at the large intestine?
excess water is absorbed from food.
83
What does the small intestine produce?
amylase, lipase and protease enzymes to complete digestion.
84
What happens at the small enzyme?
digested food is absorbed out of the digestive system and into the blood.
85
What is the Rectum?
Where faeces ( indigestible food ) are stored.
86
How do you prepare food for food testes?
1- break up desired food using a pastel and mortar.
2- transfer food to breaker and add distilled water.
3- still mixture with a glass rod to dissolve some of food.
4- filter solution using a funnel lined with filter paper.
87
What is Benedicts solution used to test for?
Sugars
88
What time of sugar does Benedict's solution test for?
Reducing sugars.
89
How do you carry out a food test with benedict's solution?
1- Transfer 5cmcubed of a food sample to a test tube.
2-prepare a water bath set to 75 degrees.
3- add benedict's solution to test tube ( ten drops) using a pipette.
4-Using a test tube holder place test tube in the water bath for five minutes, make sure the tube is pointing away from you.
90
What colour will Benedict's solution change to?
It will turn from a blue colour to either, green, yellow or brick red depending on the amount of sugar in it.
91
What does iodine test for?
Starch
92
How do you carry out a food test with iodine?
1- add 5cmcubed of a food sample to a test tube.
| 2-add a few drops of iodine to the test tube and gently shake to mix the contents.
93
What colour will iodine go if starch is present?
It will go from browny - orange to black or black - blue
94
How do you test for lipids?
Sudan III solution
95
How do you carry out a food test using Sudan III solution?
1- add 5cmcubed of unfiltered food sample to a test tube
2- add three drops of the solution to test tube using a pipette and gently shake.
2-Sudan III solution stains lipids
96
How does Sudan III show that lipids are present?
The mixture will separate out into two layers, The top layer will be bright red.
97
Where are your lungs?
In the Thorax.
98
What is the Thorax?
The top part of your body.
99
What separates the thorax and the bottom part of your body?
The diaphragm
100
What are lungs protected by?
The rib cage.
101
What are lungs surrounded by?
Plueral membranes.
102
What does the Trachea separate into?
The bronchi going into each lung.
103
What do the bronchi split into?
Bronchioles
104
What are at the end of the bronchioles?
Alveoli.
105
What happens at the Alveoli?
Gas Exchange.
106
What surrounds the alveoli?
A network of blood capillaries.
107
What is the blood like as it passes the alveoli as it returns from the rest of the body?
Full of carbon dioxide and little oxygen.
108
How does the oxygen get from the alveoli to the blood.
It diffuses from an area of high concentration (alveoli) to the blood (low concentration).
109
How does carbon dioxide get from the blood to the alveolus?
It diffuses from high concentration (blood) to low concentration (alveolus)
110
What happens when the oxygenated blood reaches body cells?
It is released from red blood cells (High concentration) to be diffused into the body cells (low concentration)
111
How do you calculate breathing rate in BPM?
BPM = number of breaths / number of minutes.
112
What is the circulatory system?
It carried food and oxygen to every cell in the body, It also carries waste products away from the cells.
113
What is the circulatory system made up of?
The heart, The Blood, The Blood Vessels.
114
What is the double circulatory system?
Two circuits joined together.
115
What happens in the first circuit? ( of the circulatory system )
The right ventricle pumps deoxygenated blood to the lungs to take in oxygen. The blood Then Returns to the heart.
116
What happens in the second circuit? ( of the circulatory system )
pumps oxygenated blood round the body, then the deoxygenated blood returns back to the heart.
117
How does the heart pump blood round the body?
It contracts.
118
What are the walls of the heart made out of?
Muscle tissue.
119
What do valves in the heart prevent?
bloody flowing backwards.
120
How does the heart use the four chambers to pump blood around the body?
1- Blood flows into the atria from the vena carva and the pulmonary vein.
2- the atria contract pushing the blood into the ventricles
3-The ventricles contract forcing blood into the pulmonary artery and the aorta, blood flows out of the heart.
4-Blood flows through the organs through the arteries and returns through the veins
5- the atria fill again are the cycle repeats
121
What does the heart need its own supply of?
Oxygenated blood.
122
How does the Heart get its own supply of oxygenated blood?
arteries called the coronary articles branch of the aorta and surround the heart.
123
What is your resting heart rate controlled by?
A group of cells in the right atrium wall that acts as a pace maker.
124
How does your pacemaker work?
Electrical impulses spreads around the muscle cells causing the to contract.
125
What are the three types of blood vessels?
Arteries - carry the blood away from the heart
capillaries - involved in the exchange of materials at the tissues
viens - carrying blood to the heart
126
Why do the artery walls need to be strong and elastic?
To handle the pressure of the blood.
127
What is the name of the hole down the middle of an artery?
Lumen.
128
What allows the arteries to stretch and spring back?
elastic fibres.
129
Wat do arteries branch into?
Capillaries.
130
Why do capillaries carry blood close to the cell?
to exchange substances with them.
131
Why do capillaries have permeable walls?
so substances can diffuse in and out.
132
Why are capillary walls one cell thick?
It increases rate of diffusion by decreasing distance diffusion occurs.
133
Where do veins take blood?
Back to the heart.
134
What joins up to form veins?
Capillaries.
135
Why do walls of veins not have to be as thick as artery walls?
Blood isn't under such high pressure as it is when it flows through arteries.
136
Why do veins have a bigger lumen?
To help blood flow under low pressure.
137
Why do veins have valves?
To keep blood flowing in the right direction.
138
How do you calculate the rate of blood flow?
Rate of blood flow = volume of blood / number of minutes
139
What is rate of blood flow measured in?
ml/min
140
What is the blood as a whole?
a tissue.
141
What do red blood cells carry?
oxygen.
142
What shape do red blood cells have?
Bioconcave disk.
143
Whats the advantages of re blood cells being bioconcave?
Gives a larger surface area to absorb oxygen.
144
Why don't Red Blood Cells have a nucleus?
To make more space to carry oxygen.
145
What else do red blood cells contain?
A red pigment call Haemoglobin.
146
What does haemoglobin become when it binds to oxygen in the lungs?
oxyhaemoglobin.
147
How do red blood cells release oxygen to body tissues?
Oxyhaemoglobin splits up into oxygen and haemoglobin to release oxygen to cells.
148
What do white blood cells defend against?
Infection.
149
What is the process called when white blood cells shape to engulf unwanted microorganisms.
Phagocytosis.
150
What do white blood cells produce and release?
Antibodies
151
What do antitoxins do?
neutralise any toxins produced by the microorganisms.
152
What do white blood cells have that red blood cells don't?
a nucleus.
153
What do platelets help with?
blood clotting.
154
What are platelets?
small fragments of cells that don't contain a nucleus.
155
What do lack of platelets cause?
excessive bleeding and bruising
156
What is plasma?
A liquid that carries everything in the blood.
157
What does Plasma carry?
- red and white blood cells
- nutrients (glucose and amino acids)
- carbon dioxide
- urea from liver to kidneys
- hormones
- proteins
- antibodies and antitoxins
158
What does 'cardio vascular disease' describe?
It describes diseases of the heart or blood vessels.
159
Give an example of a cardiovascular disease
Coronary heart disease
160
What can help prevent coronary heart disease?
Stents and Statins.
161
What do stents do?
Keep arteries open.
162
What is coronary heart disease?
when the coronary arteries get blocked by layers of fatty material. making the arteries narrow and restricting blood flow. There is a lack of oxygen to the blood which may lead to a heart attack.
163
What are stents?
Tubes that are inserted inside arteries to keep them open, keeping a persons heart beating and keeping them alive.
164
What are the advantages of using stents?
- They lower the risk of a heart attack
- They are effective for a long time
- Short recovery time
165
What are the disadvantages of using stents?
- There is a res of complications during the surgery (e.g heart attack)
- Risk of infection
- Risk of patient developing blood clot near the stent
166
What is a blood clot close to a stent called?
Thrombosis.
167
What do statins reduce?
Cholesterol in the blood.
168
What is cholesterol?
An essential lipid in your body and is essential for the body to function properly.
169
Is there a down side to cholesterol?
too much cholesterol can cause health problems (e.g LDL cholesterol)
170
What are statins?
Drugs that can reduce the amount of cholesterol present in the bloodstream. Slowing down the rate of fatty deposits forming
171
What are the advantages of statins?
- Statins can reduce the risk of strokes, coronary heart disease and heart attacks
- statins increase the amount of beneficial type of cholesterol (HDL cholesterol) Thus type can remove bad cholesterol from the blood
- studies suggest that statins may help prevent some other diseases
172
What are the disadvantages of Statins?
- a long term drug taken regularly, there is a risk of forgetting to take them
- negative side effects e.g headaches
- serious side effects e.g kidney failure and liver damage
- effect of statins isn’t instant and takes time for the effect to kick in
173
Are artificial hearts temporary?
yes
174
What are the advantages of artificial hearts?
- less likely to be rejected by the immune system than a donor heart.
175
Why are artificial hearts less likely to be rejected by the bodies immune system?
They are made from plastics and metals so the body doesn't recognise them as a foreign attack the same way it does with a living tissue.
176
What are the disadvantages of artificial hearts?
- surgery to fit artificial hearts and transplant surgery can lead to bleeding and infection.
- they don't work as well natural hearts, parts could wear out and the electrical motor could fail.
- blood doesn't flow through artificial hearts easily leading to blood clots then strokes.
177
How do doctors make it easier for blood to flow through artificial heart?
The patient takes drugs to thin the blood.
178
What are faulty heart valves replaced with?
Biological or mechanical valves.
179
What can heart valves be weakened by?
Heart attacks, infection or old age.
180
What can damage of the heart valves cause?
the valve tissues stiffen so it won't open correctly or may begin to leak which would allow blood to flow or both directions instead of just forward.
181
What happens when valves become leaky and don't open properly?
Blood doesn't circulate properly and effectively.
182
How is severe heart valve damage treated?
By replacing the heart valve.
183
Where do replacement heart valves come from?
Humans or other mammals (cows or pigs)
184
What are heart valves taken from mammals called?
Biological valves
185
What are man-made heart valves called?
mechanical valves
186
What are the advantages of using valves?
It's a less drastic procedure than a whole heart transplant.
187
Wha are the disadvantages of using heart valves?
Fitting artificial valves is still major surgery and there can still be problems with blood clots.
188
What is artificial blood?
a blood substitute. e.g a salt solution 'saline' is used to replace the loss amount of blood.
189
Is artificial blood safe?
Yes as long as no air bubbles get into the blood.
190
What are the advantages of artificial blood?
- It can keep people alive even if they loose 2/3 of their red blood cells.
- it gives people time to produce new blood cells, if not they may need a blood transfusion.
191
What is a major cause of ill health?
Disease
192
What are the two catorgories of diseases?
-communicable
or
-Non-communicable
193
What are communicable diseases?
Diseases that are spread from person to person or between animals and people.
194
What are communicable diseases caused by?
Bacteria, Viruses, Parasites and fungi.
195
What are communicable diseases sometimes described as?
Contagious or infectious diseases
196
Give two examples of communicable diseases.
Measles and malaria.
197
What are non-communicable diseases?
those not spread between people or animals.
198
What are the characteristics of non-communicable diseases?
They last for along time and get worse slowly.
199
Name three examples of non-communicable diseases.
Asthma, Cancer and Coronary heart disease
200
If you have a problem with your immune system why would you have an increases chance of suffering from communicable diseases?
The body is less likely to defend itself from the pathogen that causes the disease.
201
What non-communicable disease can be triggered by infection and viruses?
Some types of cancer.
202
What can mental health issues be triggered by?
suffering from severe mental health problems. particularly if the health problems affect everyday activities or life expectancy.
203
What other factors effect health?
- diet (whether or not you have a good, balanced diet)
- Stress
- Life situation (easy access to medical help, or ways to prevent you from getting ill.)
204
What do risk factors increase your chance of?
Getting a disease
205
What are risk factors?
aspects or someones lifestyle (e.g exercise) or the presence of certain substances in the environment e.g air pollution.
206
What are many non communicable diseases caused by.
several different risk factors interacting with each other.
207
Give examples of where risk factors have directly caused disease.
smoking has been proven to directly cause cardiovascular disease, lung disease and lung cancer. It damages the walls of arteries and cells in the lining of the lungs.
208
What is cancer caused by?
uncontrolled cell growth and division.
209
What is a tumour?
A mass of cells
210
What are the different types of Tumours?
Benign or Malignant.
211
What are benign tumours?
Where the tumour grows till there is no more room. The tumour stays in one place rather than invading other tissues in the body. This type isn't cancerous and isn't normally dangerous.
212
What are malignant tumours?
where the tumour grows and spreads to neighbouring healthy tissues. cells can break off and spread to other parts of the body by travelling in the blood stream. The malignant called evade healthy tissues and form secondary tumours. Malignant tumours are dangerous and can be fatal - They are cancerous.
213
How is Obesity a risk factor for cancer?
It is linked to bowel, liver and kidney cancer.
214
What are people who live in sunny climates more at risk of?
UV exposure and skin cancer.
215
What viruses increase the risk of getting liver cancer?
Hepatitis B and Hepatitis C. These can be spread by unprotected sex and sharing needles.
216
What else can risk factors can be associated with?
genetics
217
What are plant cells organised into?
Tissues and organs
218
Name examples of plant tissues.
```
Epidermal tissue
Palisade mesophyll tissue
Spongy mesophyll tissue
Xylem and phloem
Meristem tissue
```
219
What is the epidermal tissue?
It covers the whole plant.
220
What are the palisade mesophyll tissues?
Where photosynthesis happens.
221
what are the Spongy mesophyll tissues?
It contains big big air spaces to allow gasses to diffuse into the cells.
222
What are the xylem and phloem vessels?
They transport things like water, mineral ions and food around the plant.
223
What is the meristem tissues?
found at the growing tips of shoots and roots and is able to differentiate into lots of different types of cell.
224
Why are epidermal tissues covered with a waxy cuticle?
To reduce water loss by evaporation.
225
Why is the upper epidermis transparent?
so the light can pass into the palisade layer.
226
Why does the palisade layer have lots of chloroplasts?
the palisade layer is at the top of the leaf so it means chloroplasts are at the top and get the most light.
227
The xylem and phloem form a network of what?
Vascular bundles.
228
How are the tissues of the leaf adapted for gas exchange?
The lower epidermis is full of little holes called stomata which let CO2 diffuse directly into the leaf
229
What do phloem tubes transport?
Food.
230
What are phloem tubes made of?
Columns of elongated living cells with small pores in the end of the walls to allow cell sap to flow through.
231
Where do phloem tubes transport food from?
the leaves
232
which way is transportation in phloem tubes?
both directions.
233
What is the process called where by food is transported by the phloem tubes?
Translocation.
234
What do xylem tubes do?
Take water up the plant.
235
What are xylem tubes made from?
Dead cells joined at the end.
236
What are xylem tubes strengthened with?
A material called lignin
237
Where do xylem tubes carry water from?
The roots to the stem and leaves
238
What is the process of water moving from the roots through the xylem and out of the leaves called?
Transpiration stream.
239
What is Transpiration?
The loss of water from a plant
240
What is transpiration caused by?
Evaporation and diffusion.
241
Where does most transpiration happen?
At the leaves
242
How is water lost from transpiration replaced?
More water is drawn up from the rest of the plant through the xylem vessels.
243
What your things are transpiration rate affected by?
1- Light intensity
2- Temperature
3- Air flow
4- Humidity
244
Explain how transpiration is affected by light intensity.
The brighter the light the greater the transpiration rate, Stomata begins to lose in darker conditions. Photosynthesis can't happen in the dark so the don't open to let in CO2. When the stomata closes little water can escape.
245
Explain how transpiration is affected by temperature.
The warmer it is the faster transpiration happens. Particles of water have more energy in warmer conditions.
246
Explain how transpiration is affected by air flow.
The stronger the wind around a leaf the greater the transpiration rate. less particles stay close to the leaf and the concentration of particles is ,lower meaning diffusion happens quicker. If air flow is poor, water vapour just surrounds the leaf, meaning the is a high concentration of water particles so diffusion happens slower.
247
Explain how transpiration is affected by Humidity.
The drier the air around the leaf the faster transpiration happens. (the same as air flow)
248
How do you estimate the rate of transpiration?
Potometer - By Measuring the uptake of water by a plant. Water uptake is directly related to water loss. Record the amount of time it takes an air bubble to move aa certain distance.
249
What are guard cells adapted to do?
open and close stomata.
250
What kind of shape do guard cells have?
Kidney
251
What happens to guard cells when the plants have lots of water?
They fill with water and turn plump making stomata open so gases can be exchanged for photosynthesis.
252
What happens to guard cells when the plant is short of water?
the guard cells lose too much water and become flaccid making the stomata lose stoping water vapour from escaping.
253
Why are guard cells sensitive to light?
So they close at night so they save water without loosing out on photosynthesis.
254
Why do you find more stomata on the undersides of leaves?
The lower surface is shaded and cooler so less water is lost through the stomata the if they were on the upper surface.
