Biology Paper 1 GCSE Exam Flashcards
1
Q
Which cells can you find a cell wall in?
A
Plant Cell
Bacterial Cell
2
Q
Which cells can you find a cell membrane in?
A
Plant Cell
Animal Cell
Bacterial Cell
3
Q
Which cells can you find a nucleus in?
A
Plant cell
Animal Cell
4
Q
Which cells can you find a cytoplasm in?
A
Plant Cell
Animal Cell
Bacterial Cell
5
Q
Which cells can you find a Ribosomes in?
A
Plant Cell
Animal Cell
Bacterial Cell
6
Q
Which cells can you find a mitochondria in?
A
Plant Cell
Animal Cell
7
Q
Which cells can you find a chloroplasts in?
A
Plant Cell
8
Q
Which cells can you find a vacuole in?
A
Plant Cell
9
Q
Which cells can you find a flagella?
A
Bacterial Cell
10
Q
Which cells can you find a Plasmid?
A
Bacterial Cell
11
Q
How do you calculate the magnification?
A
Image height / Object height
12
Q
What is 1 micrometre in mm?
A
0.001
13
Q
What is 1 nanometre in mm?
A
0.000000001
14
Q
What is the advantage of a light microscope?
A
Easy to use and inexpensive
15
Q
What are the advantages of a electron microscope?
A
Can see smaller thing and more detail. It also has a higher resolution and magnification
16
Q
What is the resolution of an electron microscope?
A
1 nanometer
17
Q
What does magnification mean?
A
The act or process of enlarging the physical appearance or image of something.
18
Q
What is a specialised cell?
A
A cell which is adapted to carry out a particular function
19
Q
What happens when a cell differentiates?
A
It acquires different sub-cellular structures to enable it to carry out a certain function.
20
Q
What are some examples of a specialised cell?
A
ciliated cell Xylem cell nerve cell sperm cell root hair cell phloem cell red blood cell muscle cell
21
Q
What is the function of a sperm cell and how is it adapted?
A
Head contains genetic information and an enzyme to help pentrate the egg cell membrane and fertilise the egg.
22
Q
What is the function of a root hair cell and how is it adapted?
A
Has long fingers which gives it a large surface area which helps absorb water and mineral irons from the soil
23
Q
What is the function of a ciliated cell and how is it adapted?
A
Has a tiny thin layer of tiny moving hairs called cilia which push and move mucus from one place to another
24
Q
What process do cells use oxygen?
A
Respiration
25
How does the mitochondria in a sperm help it to swim>
It releases energy so it can swim
26
Why does a bacterial cell not contain mitochondria?
There is not enough room in a bacterial cell
27
Why is a leaf cell specialised to carry out photosynthesis?
It has many chloroplasts
28
```
Put this in order of size from the smallest to the largest:
Chromosome
nucleus
gene
cell
```
Gene
Chromosome
Nucleus
Cell
29
What are chromosomes made out of?
Small sections called genes
30
What is a stem cells?
An undifferentiated cell
31
When can embryonic stem cells be collected an what can they develop into?
Can be collected from early embryos and can develop into any type of cell
32
What happens after the egg and the sperm meet?
They form a zygote then divide using mitosis
33
Where does adult stem cells come from and what can they develop into?
Can be collected from adult bone marrow and can develop into many but not all types of cells
34
What are some arguments against stem cells?
An embryo is a human so it has human rights
Murder is just wrong
Killing an embryo at any age is as wrong as killing a child or an adult
Creating embryos for medical treatment is wrong. It's creating a life which is then destroyed
35
What are some arguments for stem cells?
Can cure many diseases including making new brain cells for parkinsons
rebuild bone and cartialage
If it was for you or a friend and it was the only way you could get better you wouldnt be against it
Research on embryos is legal up to 14 days and if something is legal it cant be wrong
36
What does a cell need to do before it divides?
Replicate the DNA and increase the number of sub cellular chromosomes like ribosomes and mitochondria
37
Where does mitosis take place?
Any body cell
38
How many cell divisions are there in Mitosis?
1
39
How many daughter cells are produced in mitosis?
2
40
Are the daughter cells in mitosis genetically identical or different?
identical
41
Why is mitosis important?
Cell replacement
| Growth
42
Does the daughter cells have the same number of chromosomes compared to the parent cell?
yes
43
What type of molecules can diffuse?
Gases
| Liquids
44
What is the definition of diffusion?
Spreading out of particles of a gas or dissolved molecules from a high concentration to a low concentration. Molecules diffuse down a concentration gradient.
45
What are two factors which increase the rate of diffusion?
Temperature
Concentration difference
Surface area of the membran
46
Why do living things need oxygen?
Respiration
47
What is the surface area like of a single celled organism compared to volume ratio?
Has a relatively large surface area to volume ratio. This allows sufficient transport of molecules into and out of the cell
48
What is the surface area like of a multicellular organism compared to volume ratio?
Small surface area to volume ratio means they have developed exchanges surfaces that are specialised for exchanging materials
49
What gases are exchanged in the lungs?
Oxygen
| Carbon Dioxide
50
Where in the lungs does exchange take place?
Alveoli
51
How is the alveoli stucture adapted for rapid gas exchange?
Large Surface Area
Its thin creating a short diffusion pathway
Ventelation to maintain a difference in concentration
efficient blood supply
52
What substances are exchanged in the small intestine?
Nutrients are absorbed into the blood
53
How is the small intestine for rapid exchange?
Large surface area
Thin cell wall so short diffusion pathway
Efficient blood supply
54
How are the gills in a fish adapted?
Large surface area
Thin creating a short diffusion pathway
efficient blood supply
55
How is the root adapted for rapid exchange?
Large Surface Area
| Thin creating a short diffusion pathway.
56
How does minerals enter a root hair cell?
Active transport
57
How does active transport work?
When substances move into cells from low to high concentration. It needs energy to make it happen which is released in respiration.
58
How is active transport used in the gut?
Allow sugar molecules to be absorbed from lower concentrations in the gut into the blood which has a higher sugar concentration
59
What is osmosis?
Osmosis is the movement of water molecules from a dilute solution to a concentrated solution through a partially permeable membrane.
60
Which type of movement requires energy from respiration?
Active Transport
61
What vegetable could be used to investigate osmosis?
Potato
62
How do you do the potato experiment to observe osmosis?
1. Label 6 boiling tubes with each sugar concentration (0M, 0.2M, 0.4M....1M)
2. Measure out 10cm3 of each sugar solution and place into correct boiling tubes
3. Using a cork borer, cut six potato cylinders of the same diameter
4. Trim the cylinder so that they are all the same length
5. Accurately measure and record the length and mass of each potato cylinder before placing into boiling tubes
6. Leave cylinders in boiling tubes over night
10. Remove one of the cylinders from the boiling tubes and carefully blot dry with the paper towels
11. Re-measure the length and the mass and record in your table
12. repeat with the remaining cylinders
63
What would you have found out after using the potato cylinders to observe osmosis?
As the sugar concentration increase the change in mass decreases. At a sugar concentration of 0.25m there is no change in mass
64
How can you explain what has happened to the potato cylinders?
At a concentration of 0m sugar solution the mass of the potato cylinder increases because water has moved into the potato. The potato becomes turgid.
At a concentration of 1m sugar solution the mass decreases because water has moved out. The potato has become flacid
65
What is a stem cell?
An undifferentiated cell
66
What would happen if you got stem cells from someone else?
The immune system would recognise the cell as foreign and they would be rejected and die
67
What is therapuetic cloning?
They take a nucleus out of a human egg cell then they would put the nucleus from the patients cell into the egg cell. The egg cell then stimulates to develop an embryo and then the stem cells are taken from the embryo. The stem cell is then grown in a container of warm nutrients and then treated to develop into required cell types.
68
What are plant meristem cells?
unspecialised stem cells in plants grouped together in structures
69
How are plant stem cells different to animal stem cells?
Animal stem cells stop growing in size once they become adults but plants continue to grow
70
How can we use meristem cells advantageously?
produce clones of plants quickly and economically. This means rare species can be cloned to protect them from extinction
71
What is the function of the stomata?
Carbon dioxide in
Oxygen out
Controls water loss
72
What would happen if you put red blood cells into water?
Water will diffuse in and cells will swell and burst
73
What is the definition of a tissue?
group of cells with similar structures and function
74
What is an organ?
A collection of tissues performing a single function
75
What is an organ system?
A group of organs working together to perform a function
76
Which tissue types have the stomach adapted to enable it to carry out its function?
Muscular - contracts bringing about movement
Glandular - produces substances such as enzymes and hormones
Epithelial - Cover some parts of the body
77
What are enzymes?
enzymes speed up chemical reactions in your body otherwise they would take place to keep you alive
78
What are 4 properties of enzymes?
Biological catalysts
cannot be used up
made from protein
They are specific they will only catalyze one reaction
79
What are catalysts?
Increases the rate of a chemical reaction without being used up or changed
80
What does the lock and key theory state?
It stated that a reaction to take place the substrate much fit perfectly into the active site of the enzyme. This means that enzymes are specific and will only bind with one type of substrate.
81
What does denature mean?
The shape of the active site has changed
82
Where is Amylase produced and what is its substrate and product?
```
Its produce in the:
Salivary gland
small intestine
pancreas
The substrate is starch and glucose is its product
```
83
Where is Protease produced and what is its substrate and product?
```
Produced in the:
Small Intestine
Pancreas
Stomach
The substrate is protein and amino acids it its product
```
84
Where is Lipase produced and what is its substrate and product?
Produced in the:
Pancreas
Small intestine
The substrate is lipids and fatty acids and glycerol are its products
85
What is digestion?
The process of food being broken down through your body using either mechanical digestion or enzymes
86
Why do we have enzymes to digest our food?
Speed up the break down of the food in the amount of time needed to keep us alive. The reaction would take place too slowly without
87
What happens to the products of digestion?
Absorbed by the small intestine into the blood strean
88
What type of digestion happens in the mouth?
Mechanical
89
What enzyme is produced in the salivary glands?
Amylase
90
What type of digestion happens in the stomach?
mechanical
91
What does stomach acid create?
The acidic conditions needed for protease to work
92
What does bile do?
Bile emulsifies large fat molecules to form small droplets
93
Why does bile neutralise food?
To create the alkaline conditions needed for enzymes in the small intestine to work
94
How do you test for sugars?
1. grind up food and place in a beaker with distilled water
2. stir so food dissolves and filter
3. fill half the test tube with the solution and add 10 drops of benedicts solution
4. put hot water in a beaker and place test tube in it
5. If sugar is in it it should turn green, yellow, or brick red
95
How do you test for Starch?
Add a few drops of iodine solution to the food solution and if starch is present it should turn black or a blue-black colour
96
How do you test for Lipids?
1. grind up the food sample and place into a beaker with distilled water
2. stir mixture so food dissolves but do not filter
3. fill half of the test tube with the solution
4. add 3 drops of Sudan III stain to the solution and shake gently to mix
5. If fat is present a red stained layer will seperate out and float on the water surface
97
How do you test for proteins?
1. grind up the food sample and place into a beaker with distilled water
2. stir mixture so food dissolves and filter
3. fill half of the test tube with the solution
4. add 2cm3 of biuret stain to the solution and stir
5. If protein is present it should turn the solution pink or purple
98
What does the optimum temperature show?
The temperature the enzyme works best at
99
How do you investigate the effect of pH on the enzyme amylase?
1. Place one drop of iodine solution into each depression on the spotting tile
2. Label three test tubes with pH 4, 7 and 10
3. Measure out 5cm3 of starch solution, using the measuring cylinder or syringe, into 3 test tubes
4. Measure out 5cm3 of each buffer solution and add to appropriate test tube
5. Place test tube of starch solution at pH 4 into a water bath of 37c
6. Measure out 1cm3 of amylase solution, using a measuring cylinder into a test tube and place in water bath
7. leave test tubes in the water baths until the contents of each tube have reached temperature of water baths
8. Once they've reached required temperatures carefully pour amylase solution into the test tube with the starch solution and mix with glass rod
9. Remove one drop of mixed solution on the end of the glass rode and place on first depression of the spotting tile with the iodine solution
10. Immediately start time
11. using glass rod remove one drop every minute and place into iodine solution in the next depression rinse glass rod with water after each drop
12. continue until iodine solution no longer turns black this indicates starch has been broke down
13. repeat for pH 7 and pH 10
100
What happens as the pH level gets further away from the optimum?
enzyme activity decreases
101
What is the epidermal tissue?
Covers the outside of the plant a single layer of cells that don't contain chloroplasts
102
What is the spongy mesophyll tissue?
Contains air spaces to allow gases to move freely and rapidly within the plant
103
What are guard cells?
Control the opening and closing of the stomata to regulate the movement of carbon dioxide into the leaf and oxygen out of the leaf. It also helps water loss
104
What is the meristem tissue?
Found in the buds and growing tips of roots in plants. It triggers the growth of new cells at the tips of roots and shoots
105
What is the palisade mesophyll tissue?
a tissue composed of a single layer of long cells just under the upper epidermis. They contain many chloroplasts and their primary funtion is to carry out photosynthesis
106
What are xylems and what do they do?
Transport water from the roots which gets evaported in the end. The xylem vesselds are made from dead xylem cells. They have a thick reinforced cell wall for a strong structure
107
What are phloems and what do they do?
Vessels involved in the movement of dissolved sugars. consist of living cells. end of cell walls have holes in that are called sieve plates
108
What is translocation?
The movement of dissolved sugars made in the leaves around the plant. It happens so repiration can take place.
109
What is transpiration?
evaporation of water from the leaves it causes water to be drawn into the plant. Its important because it keeps the leaves cool.
110
What type of weather will slow down transpiration?
Humid weather
111
What weather conditions speed up transpiration?
Windy, warm or ligth
112
What sort of conditions does lactose work best?
Alkaline conditions
113
What conditions does lipase work best?
Alkaline conditions
114
Why do we breathe?
So we have a supply of oxygen and get rid of carbon drioxide
115
What are the rings of cartilage in the trachea for?
To strengthen the trachea
116
What are the tiny tubes in the lungs called?
Bronche
117
What are the main air sacs in the lungs called?
Alveoli
118
What are two way alveoli are adapted for efficient gas exchange
walls are thing for gas to pass through
| large surface areas for diffusion
119
How does oxygen move into the blood from the lungs?
Alveoli
120
What is ventilation?
Movement of oxygen into the blood
121
What is the main thing in the alveoli which helps to mantain a concentration gradient
rich blood supply
122
What is the function of the bronchioles?
ensure that alveolus is supplied with air
123
What is the vein called in the heart?
Pulmonary vein
124
What is the valves called in the heart?
Cuspid valve
125
What is the top bit of the heart called?
Right/left atrium
126
What is the bottom bit of the heart called?
Right/left ventricle
127
What are the heart muscle own blood vessels called?
Coronary arteries
128
Where does the coronary arteries on the heart branch off?
aorta
129
Where does the coronary arteries supply oxygen and glucose to?
Muscular tissue that the heart is made from
130
What is the difference between the atria and the ventricles?
Ventricles are bigger and ventricles are at the bottom
131
What is the difference between the hearts left and right ventricle?
Left side has thickers walls
132
Whys does the left ventricle have thicker walls?
Because it needs to pump blood to the rest of the body
133
What are 3 types of blood vessels?
Veins
Arteries
Capillaries
134
What does the arteries do?
Carry blood away from the heart
135
Why does arteries have a thick elastic wall?
blood leaving the heart is travelling at a high speed and high pressure
136
What do veins do?
Carry blood to the heart
137
Why do veins have thinner elastic walls that arteries?
blood is travelling slower and at a lower pressure
138
What do veins carry?
deoxygenated blood apart from the pulmonary vein
139
What do capillaries do?
transport blood from arteries to every body cell and then into the veins
140
Why are capillaries only one cell thick?
To create a small diffusion pathway between the blood and the cells
141
What do platelets do?
helping the blood to clot at a wound
142
What do white blood cells do?
destroys pathogens
| produces antibodies
143
What factors can affect your health?
```
smoking
excercise
unbalanced diet
hygeine
weathe
```
144
What are communicable disease?
cause symptoms which let you know you have the disease.
145
What is a pathogen?
microorganism that causes disease
146
What are two types of pathogens?
Virus
| Bacteria
147
What do bacteria and viruses do?
Reproduce rapidly inside the body and produce toxins which make us feel ill
148
Why do viruses make us feel ill?
they reproduce inside cells and causes damage
149
How can pathogens spread?
direct contact by bodily fluid and in the air
150
How can you reduce contact with infected individuals?
Quarantine measures by isolating infected individuals
151
How can the spread of disease be avoided?
Reduce contact with infected person
Practising good hygeine methods
vaccination
152
What do vaccinations do?
exposes your immune sustem to a particular pathogen so that it can develop an antibody to fight it
153
What are 4 types of pathogens?
Bacteria
Protist/parasite
Virus
Fungal
154
What is an example of a disease caused by a bacteria pathogen?
Tuberculosis
155
What are some symptoms for tuberculosis?
```
Lack of appetite
Weight loss
fever
night sweats
extreme tiredness
fatigue
```
156
How does TB spread?
someone that is infected coughs and sneezes and someone else inhales the expelled droplets
157
How can you prevent TB?
Isolation
| Vaccination
158
What is and example of a disease caused by a protist/parasite?
Malaria
159
What are some symptoms of Malaria?
```
Vomiting
Fever
Headache
sweats
Chills
```
160
How does Malaria spread?
Bites of infected mosquitoes
161
How can you reduce or prevent malaria?
find out if you are at risk
avoid getting bites
malaria prevention tablets
162
What is an example of a disease cause by a virus pathogen?
Ebola
163
What are some symptoms of Ebola?
```
Vomiting
Diarrhea
Red eyes
Raised rash
Chest Pain
Stomach Pain
Weight loss
Bleeding usually from eyes
```
164
How does Ebola spread?
through human to human transmission via direct contact, blood, organs or bodily fluid
165
How can you reduce or prevent Ebola?
avoid areas of outbreak
wash hands
avoid contact with infected people
don't handle remains
166
What is an example of a disease caused by a fungal pathogen?
Atheletes foot
167
What are the symptoms of Atheletes foot?
```
affected areas may be:
dry, red, scaly and flaky
white, soggy and cracked
itchy
sore
covered in small bllisters
```
168
How does atheletes foot spread?
don't keep feet clean
wearing shows that causes your feet to sweat
share towels, shoes and socks
walking around barefooted where fungal infections can spread
169
How can you prevent or reduce atheletes foot?
```
dry feet after cleaning
wear cotton socks and roomy shoes
wear a fresh pair of socks everyday
change shoes
not walking around barefooted
use talcum powder on feet
```
170
What are some symptoms for rose black spot for plants?
Black spots on leaf
discolouration of leaves
leaves falling off trees
171
What will happen when the plant gets rose black spot?
leaves will fall off and the plant will eventually die
172
What does rose black spot prevent?
photosynthesis
173
How many people are killed by malaria each year?
0.5 million
174
What type of blood cell do the malaria parasites invade?
Red blood cells
175
What does the malaria parasites do to the blood cells they invade?
digest the haemoglobin, grow and divide
176
What happens when the malaria parasites are released from the red blood cells?
They invade new cells and destroy the red blood cells completely
177
What are the consequences of the malaria parasite multiplying and spreading in our body?
Become anaemic
blocks you blood vessels by fragments of detroyed red blood cells
would not have enough energy as red blood cells carry oxygen around the body
178
What is the mode of transmission for salmonella?
eating contaminated food
spread from person to person by poor hygeine
Caused by bacteria
179
What are some symptoms of salmonella?
diarrhea
stomach cramps
vomiting
fever
180
How can you treat salmonella?
antibiotics
hospital care
rehydration solution
181
How can you prevent salmonella?
cook poultry fully
| do not eat or drink raw eggs
182
What is the mode of transmission for gonorrhoea?
a sexually transmitted disease
| caused by a bacterium
183
What are some symptoms for gonorrhoea?
Pain on urinating
| discharge from genitalia
184
How can you treat gonorrhoea?
Antibiotics
185
How can you prevent spread of gonorrhoea?
use of barrier method of contraception e.g condom
| Treatment with antibiotics
186
What is the mode of transmission for measles?
Person to Person through the air
187
How can you treat measles?
Ibuprofen
plenty of water
damp cotton wool on eyes
188
How can you prevent spread of measles?
Vaccine once at 13 months and one at 4 years old
189
What is the mode of transmission for HIV?
Sexually
190
What are some symptoms of HIV?
```
Rapid weightloss
Extreme tiredness
sores of the mouth, anus or genitals
Diarrhea
Pneumonia
Recurring fever
```
191
What is the treatment for HIV?
N/A
192
How can you prevent the spread of HIV?
Get tested and treated for STDs
Don't inject drugs
HIV Vaccine
193
What is the mode of transmission for TMV?
A virus spread through direct contact
194
What are some symptoms for TMV?
A distinct mosaic like pattern on the leaves
| Discolouration of the leaves, which affects the plants growth due to lack of photosynthesis
195
What is the treatment for TMV?
N/A
196
How can you prevent the spread of TMV?
Remove or discard infected plant
| remove weeds as these may harbour the virus
197
What does our immune system protect us from?
different pathogens
198
How many categories are our immune system split into and what are they?
2
1. stops pathogens getting in - first line defence
2. destroys pathogens once they've invaded - second line
199
How does the skin prevent pathogens entering?
provides a barrier that is inpenetrable to most pathogens
200
How does the eyelashes prevent pathogens entering?
Sweep foreign objects away from the eye
201
How do tears prevent pathogens entering?
Flushes pathogens/debris out of the eye
202
How does the nose/trachea prevent pathogens entering?
contains mucus which traps the pathogens
| contains hairs to sweep mucus out of the body
203
How does the stomach prevent pathogens entering?
contains hydrochloric acid to kill/destroy pathogens
204
What are two ways in which pathogens make us feel unwell?
destroy and damage cells
| release chemicals that are toxins
205
What does Phagocytes detect?
pathogens or toxins they produce
206
How do phagocytes detroy pathogens through the process phagocytosis?
1. phagocyte can detect the pathogen and move towards it
2. phagocyte recognises chemical markers on the surface of pathogens or toxins it produces. The phagocyte then binds to the pathogen.
3. The phagocyte pushes a sleeve of cytoplasm out and around the pathogen this begins the engulfing stage
4. Once engulfed the pathogen is broken down by digestive enzymes
207
What are two components of our second line defense?
1. antibodies
| 2. antitoxins
208
How does antibodies destroy pathogens?
They are specific
| Antibodies destroy pathogens by binding to them and causing them to be cut open
209
How does antitoxins destroy pathogens?
detect and bind to the to toxins, neutralising them which makes them less harmful
210
What does a vaccine introduce?
a small quantity of an inactive or dead form of pathogen into the body
211
How do vaccines work?
Vaccines causes the lymphocytes to produce antibodies to fight the infection
212
What do antibiotics treat?
Bacterial infections
213
What do steroids do?
Increase muscle growth
214
What does caffeine do?
makes you become more alert and increase concentration
215
What do statins do?
Reduce blood cholestral
216
What do pain killers do?
relieve the symptoms of disease
217
What does Thalidomide do?
Treat Leprosy
218
Why do we test drugs before selling/prescribing them?
```
Identify side effects
Make sure it is safe and find a safe dosage
Test the toxicity
Figure out the cost
Find out how effective the drug is
```
219
Why is it difficult to destroy viruses?
they replicate inside our cells
220
What is a non communicable disease?
a disease that is not caused by a pathogen
221
What are 4 examples of non communicable diseases?
Cancer
Coronary heart disease
diabeties
Obesity
222
What is a risk factor?
something that can make you more likely to suffer from a disease
223
What are some examples of risk factors for non-communicable diseases?
Unbalanced or unhealthy diets
Alcohol consumption
Lack of excercise
exposure to sun
224
What is a benign tumour?
a growth of abnormal cells which are contained in one area
225
What is a malignant tumour?
cancerous which invades neighbouring tissues and spread to different parts of the body in the blood
226
How do tumours spread?
blood
227
What does coronary heart disease affect?
The coronary arteries which will provide oxygen and glucose to the heart muscle
228
What are two things that lead to myocardial infarction?
Atheromas
| Thrombosis
229
What is atheroma and how is it formed?
name of the fatty deposit which forms within the walls of an artery. White blood cells acluminate and form a plaque which causes the artery to narrow
230
What is Thrombosis?
Thrombosis is when the blood flow is restricted blood pressure then increases. It causes damage t the lining of artery. Platelets start to aggreagate and lay down a blood clot. Sometimes it can become dislodged and move elsewhere.
231
What does the term myocardial infraction mean?
known as a heart attack. Its a symptom of coronary heart disease. It causes a reduced supply of oxygen to the muscle of the heart. It results in a blockage in one of the coronary arteries. If the blood clot is close to the junction of the artery and aorta the heart will stop beating.
232
What are stents?
stents are plastic things that go in your blood vessels to stop bloody clotting
233
What are 3 limiting factors
light
temperature
carbon dioxide concentration
234
What is the test for photosynethesis?
1. set up a test tube containing a boiling tube at a distance of 10cm away from the light source
2. fill the boiling tube with the sodium hydrogen carbonate solution
3. Put the pondweed into the boiling tube with the cut end at the top. Gently push the pondweed down with the glass rod
4. leave the boiling tube for 5 minutes with the lamp turned on
5. Start the stop watch and count the number of bubbles produced in one minutes
6. record results and repeat twice more at different distances
235
What does aerobic mean?
with oxygen
236
what is the symbol equation for respiration?
C6H12O6 + O2 = CO2 + H2O
237
What is the energy released during respiration used for?
Maintaining body temperature
energy for movement
chemical reactions inside the body
238
What sort of reaction is aerobic and anaerobic respiration?
exothermic
239
In which cells would you find the most mitochondria and why?
Pancreatic cell - lots of chemical reaction so hormones and enzymes can be produced. These reaction need energy to take place
Muscle cell - They need energy to contract and relax which enables us to move
Sperm cell - so it can swim to the ovum
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What is anaerobic respiration?
release of energy from glucose in the abscence of oxygen
| incomplete breakdown of glucose, meaning less energy is released than in aerobic respiration
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What is the equation for anaerobic respiration?
Glucose = Lactic acid + (some) energy
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Why do we respire anaerobically?
We respire anaerobically when there is insufficient oxygen for aerobic resperation to take place at the necessary rate
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What is the consequences of lactic acid build up?
Mildly toxic
when it builds up it causes the muscles to contract less efficiently and with less force
leads to muscle fatigue and oxygen debt
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What is oxygen debt?
The breakdown of lactic acid is an oxidation reaction
| Lactic acid +oxygen = carbon dioxide + water
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What is the definition of metabolism?
The sum of all the chemical reactions take place in your body
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What is metabolic rate?
the rate at which the chemical reactions take place in your body
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What are some factors that affect metabolism?
gender - men have a higher metabolic rate
proportion of muscle vs fat - more muscle you have a higher metabolic rate
Inheritance
Age - as you get older your metabolic rate slows down
Physical activity - the more active you are the higher the rate will be
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What are some reactions involved in metabolism?
conversion of glucose to starch, glycogen and cellulose
formation of lipid molecules from a molecule of glycerol and these molecules of fatty acids
resperation
breakdown of excess proteins to form urea for excretion
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What changes occur during exercise?
Heart rate increases
breathing increases
muscle fatigue
temperature increases
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What happens when you excercise to support the increased demand for energy?
Increasing heart rate
| Increase in breathing rate
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What does the increase in breathing rate do?
more oxygen is being taken in and more carbon dioxide is being taken out
When your breathing in oxygen more is delivered to the muscles for aerobic resperation
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What does the increased heart rate do?
means more blood being pumped round the body faster
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How is enough glucose provided for resperation?
muscles store glucose as glycogen which can be converted back to glucose for use during exercise
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Why is more energy needed during exercise?
more muscle cells are contracting and relaxing
