Revision 2 Flashcards
1
Q
What did the Human Genome Project aim to do?
2 marks
A
The Human Genome Project aimed to find every single human gene in order to make a complete map of the Human Genome.
2
Q
True or false? Scientists have discovered the function of every human gene.
(2 marks)
A
False. Scientists are still trying to find out what all the genes do.
3
Q
Describe how the Human Genome Project can help to improve Testing for inherited disorders, such as Cystic Fibrosis.
(5 marks)
A
Scientists are now better able to identify the Genes and Alleles that are suspected of causing an inherited disorder. Once an Allele that causes an inherited disorder has been identified, people can be tested for it.
4
Q
Genome research has found that there are some common genetic variations in people.
Suggest how this knowledge how this knowledge can be used to tailor treatments to specific people.
(3 marks)
A
Scientists can use this knowledge to design new drugs that are specifically tailored to people with a particular Genetic Variation.
They can also determine how well an existing drug will work for an individual.
5
Q
The Human Genome Project may allow doctors to know what genes predispose people to certain diseases.
Give 1 advantage and 1 disadvantage of this knowledge.
(6 marks)
A
It would enable people to get individually tailored advice on the best diet and lifestyle to help avoid their likely health problems.
However, it might allow employers and insurers to discriminate against those people who are genetically likely to get a disease.
6
Q
Give 2 Selection pressures that could affect an individuals chance of survival.
(6 marks)
A
E.g. predation, competition for resources (e.g food, water, mates etc.) and Disease.
7
Q
MRSA is a bacterium that is resistant to antibiotics. What does this mean?
(2 marks)
A
The Bacteria cannot be killed by antibiotics.
8
Q
Why can Bacteria evolve rapidly?
2 marks
A
Bacteria reproduce at a fast rate.
9
Q
What is meant by ‘natural selection’?
6 marks
A
Individuals with characteristics that make them better adapted to the selection pressures in their environment have a better chance of surviving and reproducing successfully.
This means the Alleles that are responsible for the useful characteristics are more likely to be passed on to the next generation.
10
Q
A population of lizards live in a desert and are preyed on by eagles. Some of the lizards are brown and difficult to see. Others are bright pink and stand out against the sand.
Which characteristic is likely to become more common in the population? Explain your answer.
(8 marks)
A
The brown colour is likely to become more common in the population due to natural selection. This is because the brown lizards are better adapted to their environment as they are less likely to be spotted and eaten by eagles.
More of the brown lizards will survive and breed and pass the Allele for their brown colour to the next generation.
11
Q
Describe how a population of bacteria can become resistant to a particular antibiotic.
(7 marks)
A
Bacteria can develop random mutations in their DNA that make them resistant to a particular antibiotic.
Antibiotic-resistant bacteria are more likely to survive and reproduce, passing on the gene for resistance.
The gene for resistance becomes more common in the population due to natural selection.
12
Q
Which scientist organised the expedition that found the 1.6 million year old Homo erectus fossil skeleton called ‘Turkana Boy’?
(1 mark)
A
Richard Leakey
13
Q
True or False? ‘Turkana Boy’ is older than the fossil skeleton of ‘Ardi’.
(3 marks)
A
False. The fossil skeleton of ‘Ardi’ is 2.8 million years older than that of ‘Turkana Boy’.
14
Q
What have fossils of hominids (human beings and their ancestors) taught us about the evolution of the brain in humans?
(4 marks)
A
Older hominids had smaller brains. This tells us that brain size has increased as humans have evolved.
15
Q
Brains aren’t preserved in fossils.
Suggest how scientists have been able to use fossil skeletons to learn about the evolution of the brain in humans.
(2 marks)
A
They measured the space taken up by the brain in the skull to find our the brain size.
16
Q
Give 2 ways in which ‘Lucy’ (a fossil of the Species Australopithecus afarensis) is different from ‘Ardi’ (a fossil of Ardipithecus ramidus).
(9 marks)
A
‘Lucy’ didn’t have an ape-like big toe.
‘Ardi’ did.
The size of Ardi’s arms and legs were more like an ape than a human, while the size of Lucy’s arms and legs were between what you would expect to find in apes and humans. Lucy had a larger brain.
The structure of Lucy’s leg bones and feet suggest that she walked upright more efficiently than Ardi.
17
Q
Axel is studying the fossil skeletons of ‘Ardi’ and ‘Lucy’. He suggests that Ardi was better at climbing trees than Lucy was.
Why does Axel think this?
(5 marks)
A
The structure of Ardi’s feet suggests they were well adapted for climbing trees.
For example - she had an ape-like big toe to grasp branches. Lucy had feet that are more adapted to walking than climbing and did not have an ape-like big toe.
18
Q
What does the complexity of a stone tool suggest about its age?
(2 marks)
A
The simpler a stone too, the older it’s likely to be.
19
Q
True or false? The movement of rock layers can affect the accuracy of dating stone tools.
(5 marks)
A
True. Dating stone tools using stratigraphy (the study of rock layers) can be inaccurate if the rock layers have moved over time.
20
Q
A diagram shows the position of stone tools within layers of rock underground.
Which tool (on flash card 23) A, B, or C, is likely to be the oldest? Explain your answer.
(6 marks)
A
Tool C is likely to be the oldest because it is found in the deepest layer. The deeper the layer of rock that a stone tool is found in, the older the tool is likely to be. This is because older rock layers are normally found below younger layers.
21
Q
Apart from stratigraphy (the study of rock layers), give 1 other method of dating stone tools.
(4 marks)
A
Stone tools found with Carbon-containing material, e.g. a wooden handle, can be dated using carbon-14 dating.
22
Q
Explain why differences between the stone tools used by each Homo species provides evidence for human evolution.
(5 marks)
A
The stone tools used by different Homo species became gradually more complex over time. This suggests that their brains were getting larger, providing evidence for evolution.
23
Q
What does classification mean in Biology?
2 marks
A
The organisation of living organisms into groups.
24
Q
Name the 5 kingdoms traditionally used in classification.
5 marks
A
- Animals
- Plants
- Fungi
- Prokaryotes
- Protists.
25
Archea are 1 of the 3 domains proposed for use in classification instead of the 5 kingdoms.
Name the other 2.
(2 marks)
Bacteria and Eukarya.
26
What type of organisms are in the domain Archaea?
| 3 marks
Prokaryotes. (They look similar to prokaryotes in the Bacteria domain, but are actually quite different.)
27
How can the genes of an organism be used to determine how closely related it is to other organisms?
(5 marks)
The sequence of DNA bases in the genes can be determined, and then the sequence can be compared to other organisms.
Those with more similar DNA sequences are more closely related to each other.
28
Explain how developments in technology have led to the proposal of splitting the Prokaryote kingdom into 2 domains.
(6 marks)
Developments in technology have led to the use of RNA sequencing.
This has been used to show that some members of the Prokaryote kingdom were not as closely related as first thought, leading to the proposal that the kingdom should be split into separate groups (Archaea and Bacteria).
29
Suggest 2 characteristics that a cattle farmer might want to develop in her cows over time using Selective Breeding.
(3 marks)
They might want to increase the size of the cattle, so that they produce more meat, and to increase the amount of milk produced by the cows.
30
What is ‘inbreeding’?
| 2 marks
Inbreeding is when closely related organisms are bred together.
31
There is some variation in size of the leaves produced by spinach plants. A farmer wants to grow spinach plants with particularly large leaves because they produce more food.
Describe how this could be achieved.
(6 marks)
Select the individuals that produce the largest leaves. Breed these together. Then select the individuals of the offspring that produce the largest leaves and breed these together.
Continue doing this with each new generation until the trait gets stronger. Eventually all of the plants will produce large leaves.
32
A farmer has used Selective Breeding to increase the yield from his tomato plants. A new Disease gets into the greenhouse. The first plant to be infected dies.
Suggest what might happen next and why.
(6 marks)
The other tomato plants in the greenhouse are also likely to die from the Disease. This is because Selective Breeding results in populations of closely related organisms with little genetic variation.
Therefore, if 1 plant has died from this disease, it is unlikely that there will be Alleles for resistance to the disease in the other tomato plants in the greenhouse.
33
What is Genetic Engineering?
| 2 marks
Genetic Engineering involves modifying an organism’s Genome to introduce desirable characteristics.
34
Give 1 useful substance that Bacteria have been Genetically modified to produce.
(2 marks)
Insulin. This can be used to treat Diabetes.
35
How can Genetically Engineered animals be used in Medicine?
| 7 marks
Human Genes that produce useful proteins can be transferred to animals such as sheep or cows. These proteins can then be extracted from the animal’s milk and be used to treat patients.
Animals that have organs suitable for organ transplantation into humans might also be produced in the future.
36
Give 1 ethical concern with using animals in Medicine (Genetically Engineered).
(4 marks)
Many Genetically Modified Embryos don’t survive and some Genetically Modified animals suffer from health problems later in life.
37
Many Genetically Modified crops contain transplanted genes that make them resistant to weedkiller.
Suggest why it could be a problem if these genes got out into the environment.
(4 marks)
The transplanted genes could be picked up by a weed. This would make the weed resistant to weedkiller, which would be a big problem for farmers if the weed spreads.
38
Describe how a scientist could insert a useful human gene into bacteria.
(9 marks)
A Restriction Enzyme is used to cut out the useful gene from the Human DNA.
The same Enzyme is used to cut open the Vector DNA, leaving both the Vector DNA and the Human DNA with sticky ends.
Ligase Enzymes are then used to join the 2 pieces of DNA to make Recombinant DNA, which is then inserted into the bacteria.
39
What is Recombinant DNA
| 5 marks
DNA produced by joining 2 pieces of DNA (Vector DNA and Human DNA) with the help of Ligase Enzymes.
40
Restriction Enzyme
| 2 marks
Enzyme that cuts out genes/fragments out of DNA for other use.
41
True or False? Communicable Diseases can be spread between people.
(3 marks)
True. Communicable Diseases can be spread between people, Non-Communicable Diseases cannot.
42
Give 2 Examples of Non-Communicable Diseases.
| 2 marks
Cancer and Heart Disease.
43
Bacteria, Viruses and Fungi are examples of Types of Pathogens.
Give 1 other example of a type of Pathogen.
(1 mark)
Protists
44
What are Pathogens?
| 2 marks
Pathogens are organisms that cause (Communicable) Diseases.
45
Give the definition of ‘Health’.
| 4 marks
A state of complete physical, mental and social well-being (not just the absence of disease or infirmity).
46
Explain how having 1 disease can affect the likelihood of a person getting another, different disease.
(3 marks)
Having 1 disease can increase the likelihood of a person getting another disease.
This is because their body may have become weakened by the first disease, so it’s less able to fight off other diseases.
47
Which type of Pathogen causes Malaria?
| 1 mark
Malaria is caused by Protist.
48
Give 1 effect that Tuberculosis has on the body of an infected person.
(2 marks)
E.g. Coughing and lung damage.
49
What would an ash tree infected with Chalara ash dieback look like?
(2 marks)
It would have lost leaves and have lesions on its bark.
50
Cholera is a disease that is spread by water.
How could a person pick up the Pathogen that causes Cholera?
(2 marks)
The Pathogen could be picked up by drinking or bathing in contaminated water.
51
Give 2 other ways that Diseases can be spread.
| 5 marks
E.g. Diseases can be spread through the air, through eating contaminated food (oral transmission), through exchanging infected bodily fluids and by being carried by an Animal Vector.
52
Why are people infected with Tuberculosis advised not to go to work or school, even if they feel well enough to go?
(4 marks)
Tuberculosis is spread through the air (air borne), so people with Tuberculosis should avoid crowded public spaces in case they spread the disease by coughing near others.
53
Explain how you can reduce the spread of Malaria.
| 4 marks
Malaria is carried by mosquitoes, so using mosquito nets and insect repellant can help reduce the spread of Malaria by preventing mosquitoes from biting people, therefore preventing people from becoming infected.
54
What is Malaria?
| 3 marks
A serious and sometimes fatal disease caused by a parasite that commonly infects a certain type of mosquito which feeds on humans.
55
Symptoms of Malaria
| 7 marks
- High temperature of 38C or above
- Feeling hot and shivery
- Headaches
- Vomiting
- Muscle pains
- Diarrhoea
56
How many types of Malaria parasites infect humans?
| 1 mark
4
57
What is Tuberculosis (TB)?
| 3 marks
TB is a bacterial infection spread through inhaling tiny droplets from the coughs or sneezes of an infected person.
58
Where does TB affect the Human Body?
| 5 marks
TB mainly affects the Lungs, but it can affect any part of the body, including the tummy (Abdomen), Glands, Bones and Nervous System.
59
Symptoms of Tuberculosis (TB)
| 9 marks
- Persistent cough; lasts more than 3 weeks and usually brings up phlegm, which may be bloody
- Weight loss
- Night sweats
- High temperature
- Tiredness and fatigue
- Loss of appetite
- Swellings in the neck
60
How can TB be treated?
| 1 mark
Antibiotics
61
How can someone contract Malaria?
| 1 mark
Mosquito bite
62
What is Chalara Ash Dieback?
| 3 marks
Fungus, originating in Asia, that kills Ash trees.
63
Chalara Ash Dieback Symptoms
| 9 marks
```
Dark patches/wilting or black discolouration in leaves
Leaves shedding
Dieback if the shoots and leaves
Lesions on trunk
Discolouration on inner bark
New growth from previously dormant buds
```
64
Cholera
| 4 marks
Cholera is an infection caused by contaminated water - it can cause severe diarrhoea. It's not found in the UK, but there's a very small risk of getting it while travelling in some parts of the world.
65
How can you catch Cholera?
| 4 marks
- Drinking unclean water
- Eating food (particularly shellfish) that's been in unclean water.
- Eating food that's been handled by an infected person.
66
Symptoms of Cholera
| 6 marks
- Profuse watery diarrhea, sometimes described as “rice-water stools”
- Vomiting
- Thirst
- Leg cramps
- Restlessness or irritability
67
True or False? Chlamydia is caused by a Bacterium.
| 1 mark
True
68
Which Disease is eventually caused by HIV?
| 5 marks
AIDS (Acquired Immune Deficiency Syndrome)
69
What Cells in the Body are killed by HIV?
| 1 mark
White Blood Cells
70
HIV can be spread by Sexual Contact.
Give 1 other way that HIV can be spread.
(3 marks)
E.g. The sharing of needles between drug users. This is because HIV spreads through the exchange of bodily fluids, and sharing needles can cause the exchange of blood.
71
The spread of HIV can be reduced by wearing a condom when having sex.
Give 1 other way of reducing the spread of HIV.
(4 marks)
Drug users avoiding sharing needles, using medication (to reduce the risk of infected individuals passing the virus on to others during sex or of infected mothers passing the virus to their babies during pregnancy).
72
Explain why someone infected with AIDS is very vulnerable to be infected by other Pathogens.
(4 marks)
AIDS causes an infected person’s Immune System to deteriorate and eventually fail. As a result, they are less able to fight off infections from other Pathogens.
73
When does HIV develop into AIDS?
| 1 mark
After the virus has severely damaged the Immune System.
74
What Chemical that kills Bacteria is found in tears?
| 1 mark
Lysozyme
75
Which Proteins on the surface of Pathogens trigger an immune response?
(1 mark)
Antigens
76
What is the role for the skin in protecting the body from Pathogens?
(2 marks)
The skin acts as a physical barrier that stops Pathogens from entering the body.
77
How does the Stomach help to defend the body against Pathogens?
(3 marks)
The Stomach produces Hydrochloric Acid, which kills most Pathogens that are swallowed.
78
How do Cells in the Trachea and Bronchi help to protect the Airway from Pathogens?
(5 marks)
Some cells in the Trachea and Bronchi produce Mucus, which traps Pathogens.
Other cells have Cilia, which move the mucus up to the back of the Throat so it can be swallowed.
79
Describe the role of Antibodies in the Immune System’s response to a Pathogen.
(3 marks)
Antibodies bind to the Pathogen so it can be found and destroyed by the WBC’s.
80
How is the Immune System able to attack only the invading Pathogen, and not other cells within the body?
(5 marks)
The Antibodies that are produced in an immune response are specific to the invading Pathogens.
This means that they will only bind to the Pathogen and not to other cells, so it is only the Pathogen that is then destroyed by WBC’s.
81
What are Antigens?
| 5 marks
Antigens are substances that cause an immune response in the body by identifying substances in or markers on cells.
Your body produces antibodies to fight antigens, or harmful substances, and tries to eliminate them.
82
What are Antibodies?
| 6 marks
Antibodies (aka immunoglobulin) are protective proteins produced by the immune system in response to the presence of a antigen.
Antibodies recognize and latch onto antigens in order to remove them from the body.
83
Give an Example of substances regarded by the body as Antigens.
(3 marks)
Disease-causing organisms and toxic materials such as insect venom.
84
What are foreign substances known as?
| 1 mark
Antigens
85
What is a foreign body (FB)?
| 2 marks
A foreign body is any object originating outside the body of an organism.
86
Immunisation involves injecting Pathogens into the body.
Why don’t these Pathogens cause Disease?
(2 marks)
Because the Pathogens that are injected into the body are dead or inactive.
87
What are Memory Lymphocytes?
| 5 marks
Memory Lymphocytes are a type of WBC produced in response to the Antigens of Pathogens.
They stay in the body for a long time and produce Antibodies against the specific Pathogen.
88
Outline how immunisation protects a person from future infections.
(8 marks)
The person is injected with a small amount of dead or inactive Pathogens. The Antigens on the Pathogens trigger the production of both Antibodies and Memory Lymphocytes.
In the future, if the person is infected by live Pathogens of the same type, then the Memory Lymphocytes can rapidly produce the Antibodies needed to kill it off.
89
Why is the secondary immune response much faster than the response of the Immune System when it first encounters a Pathogen?
(6 marks)
When a Pathogen enters the body for the first time, the response is slow because there aren’t many WBC’s that can make the correct Antibody.
The secondary immune response is faster because there are already a lot of Memory Lymphocytes in the body that can produce the Antibody.
90
Getting chickenpox is more dangerous if you’re an adult than if you’re a child.
Why do you think some parents deliberately expose their children to chickenpox?
(4 marks)
Once they’ve had the Disease, the children will probably have become immune to it. The parents may therefore think it’s better for their children to have the disease now than risk them getting it when they’re adults, which could be more dangerous.
91
True or False? Antibiotics are used to treat Viruses.
| 2 marks
False. Antibiotics only work on Bacteria.
92
What does it mean when patients are given a Placebo?
| 2 marks
They have been given a substance that looks like the real drug, but doesn’t do anything.
93
Give 1 reason why a drug is tested on healthy volunteers during Clinical Testing.
(2 marks)
To make sure the drug doesn’t have any harmful side effects when the body is working normally.
94
What can scientists learn from giving a drug to live animals during Preclinical Testing?
(3 marks)
Scientists can learn whether the drug works, how toxic it is and the best dosage to use.
95
Scientists have discovered 2 new drugs that kill Bacteria. Drug A works by destroying DNA, while Drug B works by breaking down Bacterial Cell Walls.
Suggest which drug is most likely to be useful as an antibiotic for treating humans.
(6 marks)
Drug B is most likely to be useful as an antibiotic because humans don’t have Cell Walls do the human host won’t be affected by the drug.
Drug A could destroy the DNA of the human host as well as the DNA of the Bacteria, so it’s unlikely to be useful as an Antibiotic.
96
A Pharmaceutical Company is Testing a new drug. Explain how a Double Blind Trial would be useful to test how well this drug works on a group of patients.
(8 marks)
Patients are randomly split into 2 groups. 1 group is given the drug and the other group is given a Placebo.
In a Double blind Trial, neither the doctors nor the patients know which patients have been given the drug and which have been given the placebo until after the results have been gathered. This is so that no one is influenced by their knowledge. The results from both groups are compared to learn how well the new drug works.
97
Name 1 organ that is affected by drinking too much alcohol.
| 3 marks
Liver - drinking too much alcohol can lead to Liver Disease.
98
Give 2 risk factors for Obesity
| 3 marks
Not getting enough exercise and having a diet too high in fat and sugar.
99
What causes Malnutrition? Why is it a problem in developing countries?
(4 marks)
Malnutrition is caused by having a diet with too many or too few nutrients. It’s a problem in developing countries because people are not able to access enough food.
100
Suggest why there is more pressure on the resources of local hospitals in areas with higher rates of obesity.
(5 marks)
Obesity is a risk factor for other Non-Communicable Diseases, such as Cardiovascular Disease.
An area with a higher rate of Obesity is therefore likely to have a higher occurrence of these diseases, so the local hospitals will be under more pressure to treat all the people who suffer from them.
101
Explain why smoking increases the likelihood of someone having a heart attack.
(11 marks)
Nicotine in cigarette smoke increases Heart Rate, which increases Blood Pressure.
High BP damages Arterial walls, which contributes to the build up of Fatty Deposits in the arteries. These deposits restrict blood flow and increase the risk of a Heart attack. Smoking also increases the risk of Blood Clots forming in arteries, which can restrict or block blood flow, leading to a Heart Attack.
102
Doctors can never be sure that smoking is the only reason why a patient has Cardiovascular Disease, even when the patient is a heavy smoker.
Explain why.
(3 marks)
Cardiovascular Disease is often caused by several different risk factors interacting with each other, rather than 1 factor alone.
103
Godfrey eats a lot of food rich in sugar and fat. He does very little exercise.
Is Godfrey’s Body Mass Index (BMI) likely to be high or low?
(2 marks)
High. Godfrey is likely to be taking in more energy than he uses.
104
What equation is used to calculate someone’s BMI?
| 7 marks
BMI = mass (kg) / (height (m))^2
105
Explain how to calculate Body Mass Index (BMI).
| 7 marks
BMI = Mass (kg) divided by height (m) squared.
106
Walter the robot is 3m tall and has a mass of 450kg.
Calculate his BMI - Explain in detail.
(16 marks)
BMI = mass (kg) / (height (m))^2
= 450 / 3^2 = 450 / 9 = 50kg m^2
107
What is the significance of having a higher waist-to-hip ratio?
(3 marks)
The higher someone’s waist to hip ratio is, the more weight they’re likely to be carrying around their middle and the greater the risk of them developing obesity-related health problems.
108
The circumference of Dorothy’s waist is 75cm and the circumference of her hips is 100cm.
Calculate her waist-to-hip ratio.
(8 marks)
Waist-to-hip ratio = waist circumference / hip circumference
= 75 / 100 = 0.75
109
Explain how to calculate the waist-to-hip ratio.
| 4 marks
Waist-to-hip ratio = waist circumference / hip circumference
110
Muscle has a higher mass than fat.
Based on this, explain why BMI is not always a reliable measure of obesity.
(6 marks)
People with lots of muscle have a high mass, so their BMI will be high and they might be classified as overweight or obese.
However, these people are likely to do lots of exercise and actually be healthy. BMI is therefore not a reliable measure of obesity in these cases.
111
What are antihypertensives?
| 2 marks
Antihypertensives are drugs that reduce blood pressure.
112
Why does a patient need to take drugs after being given a donor heart?
(2 marks)
To stop the Immune System rejecting the donor heart.
113
What is a stent? How do stents reduce the risk of heart attacks?
(4 marks)
A stent is a tube that is inserted inside an Artery. Stents keep arteries open, making sure blood can pass through to the heart muscles, lowering the risk of a heart attack.
114
Give 1 benefit and 1 risk of taking anticoagulants.
| 4 marks
Anticoagulants can reduce the risk of having a Heart Attack or Stroke by making Blood Clots less likely to form. However, they can cause excessive bleeding if the person is hurt in an accident.
115
Angelica has developed Cardiovascular Disease.
Describe the lifestyle changes she could make to reduce the risk of having a Heart Attack or Stroke.
(6 marks)
Angelico’s risk of having a Heart Attack or Stroke would be reduced if she eats a healthy, balanced diet which is low in Saturated Fat, exercises regularly, loses weight (if necessary) and does not smoke.
116
How might Statins treat Cardiovascular Disease?
| 4 marks
Statins reduce Cholesterol in the Bloodstream, slowing down the rate at which fatty deposits form and therefore reducing the risk of Heart Attacks and Strokes.
117
Suggest why a doctor might recommend lifestyle changes first to a person with Cardiovascular Disease, rather than recommend Heart Surgery straight away.
(8 marks)
Lifestyle changes can reduce the risk of a Heart Attack or Stroke and don’t have any major downsides. If a patient has Heart Surgery there is a risk of bleeding, clots and infection, so the patient should only have surgery when it is really necessary.
118
Benefits of using Medication to treat Cardiovascular Disease
(7 marks)
- Reduce low density lipoprotein cholesterol.
- Improve blood flow.
- Regulate heart rhythm.
- Prevent Heart Attacks or Strokes.
119
Risks of using Medication to treat Cardiovascular Disease
| 15 marks
- Blood thinners(anticoagulants) reduce clotting time which could lead to heavy blood loss if injured/menstruating.
- Frequent use of Statins can lead to Liver damage or Type 2 Diabetes (high blood sugar levels).
- Side effects of meds include; cognitive issues, muscle weakness, dizziness, head or stomach aches.
120
Benefits of Surgery to treat Cardiovascular Disease
| 11 marks
- Coronary Artery Bypass; Improves Blood Flow and Oxygen supply to the Heart.
- Aortic Valve Replacement; Replaces faulty valve with new functioning Valve, most affective treatment of Aortic Valve conditions.
- Surgery prevents heart failure, a Heart Attack or Stroke.
121
Risks of Surgery to treat Cardiovascular Disease
| 11 marks
Complications can lead to;
- Wound/lung/Bladder/Heart Valve infections.
- Blood clots
- Strokes
- Heart Attack
- Arrhythmia (abnormal heart rhythm)
- Reduced Kidney Function for a few days
122
Benefits of Cardiac Rehabilitation to treat Cardiovascular Disease
(13 marks)
- Can improve overall health - physically and mentally.
- Can be done at home.
- Increases Blood Flow and Oxygen supply to the Heart.
- Decreases the need for Surgery.
- Can reduce the risk of Heart Attacks, Strokes or Diabetes.
- Reduce Angina and breathlessness.
123
Cons of Cardiac Rehabilitation in the Treatment of Cardiovascular Disease
(7 marks)
- Will not abolish the risk of having a Heart Attack/Stroke; Too little exercise or eating too much can cause either regardless.
- You may still need Surgery or medication.
- May do little for a persons Anxiety of having a Heart Attack.
124
True or False? Photosynthesis is an exothermic reaction.
| 4 marks
False. Photosynthesis is an endothermic reaction. This means that energy is transferred from the environment to the plant.
125
What is Biomass?
| 2 marks
The mass of living material.
126
What is an endothermic reaction?
| 3 marks
A chemical reaction in which energy is taken in from the environment.
127
What is an exothermic reaction?
| 4 marks
A chemical reaction in which heat is produced and released out into the environment from a source.
128
Complete the word equation for photosynthesis:
1.__________ + 2.__________ —light—>
Glucose + 3.__________
(3 marks)
1. Carbon Dioxide + 2. Water —light—>
| Glucose + 3. Oxygen
129
Explain why Photosynthetic organisms are described as the main producers of food for nearly all life.
(9 marks)
The energy stored in the Biomass of Photosynthetic organisms is passed along the food chain as animals eat the Photosynthetic organisms. These animals are food for other animals. So most of the life on Earth is supported by Photosynthetic organisms.
130
Egan wants to investigate the effect of light intensity on the rate of Photosynthesis of Algae. His set up contains; gas syringe, algal balls and a lamp.
Suggest how Egan could vary the light intensity.
(4 marks)
By varying the distance of the lamp from the Algae. The further away the lamp is, the lower the light intensity will be.
131
Why would you use a Gas Syringe when investigating the effect of light intensity on the rate of Photosynthesis of Algae?
(5 marks)
To measure the volume of Oxygen produced by the Algae over a period of time. He can use this to calculate the rate of O2 production, which corresponds to the rate of Photosynthesis.
132
Give the inverse square law
| 7 marks
Light intensity ∝ 1 / distance (d)^2
133
What are the distances and (light) intensities if the Inverse Square Law is:
I1/I2∝ d22/d21
(6 marks)
Intensities - I1 and I2
Distances - D1 and D2
134
If there’s enough light and CO2, what factor could limit the rate of Photosynthesis?
(1 mark)
Temperature
135
A graph shows the rate of photosynthesis of 2 healthy plants. A and B as light intensity increases. Both plants are grown at a temperature of 25°C, but plant A is grown at 0.08% CO2 and Plant B is grown at 0.8% CO2. Line A on the graph slowly moves up at a right angle until it reaches point X - it then slows down and curves.
Line B similarly moves slowly until point X before jolting into a larger curve.
Explain the shape of the curves before point X.
(6 marks)
Before point X, light intensity is the limiting factor of Photosynthesis. As light intensity increases, the rate of Photosynthesis also increases.
136
A graph shows the rate of Photosynthesis for 2 healthy plants. A and B, as light intensity increases. Both plants are grown at a temp of 25°C, but Plant A is grown at 0.08% CO2, and Plant B is grown at 0.8% CO2.
Why does the curve for Plant A level off at a lower rate of Photosynthesis than the curve for Plant B?
(6 marks)
Carbon dioxide is limiting the rate of Photosynthesis of Plant A, because it was grown at a lower concentration of CO2, than Plant B. Since both plants were grown at 25°C temperature can’t be limiting the rate of Photosynthesis.
137
When a light source was 10cm from a plant, the light intensity was 0.04 a.u.
Calculate the light intensity when the light source was 5cm from the plants.
(9 marks)
0.16 a.u. The distance between the light source and the plant would be halved from 10cm to 5cm, so the light intensity would be 4 times greater: 0.04 a.u. x 4 = 0.16 a.u.
138
In an equation when a light source was 10cm from a plant, the light intensity as 0.04 a.u.
When the light source is 5cm for the plant the light intensity would be 4 times greater.
How is this the case?
(10 marks)
According to the Inverse Square Law;
The light twice as far from the source is spread over 4x the area, hence 1/4 the intensity.
Half of this would mean the light is spread within a contained area (1x) the light being as bright but more intense
139
What factors influence Photosynthesis?
| 3 marks
- Light intensity
- Carbon dioxide concentration
- Temperature
140
What factors are needed for Photosynthesis?
| 4 marks
- Water
- Carbon Dioxide
- Sunlight
- Chlorophyll
141
What is translocation? In which tissue does it take in a Plant?
(3 marks)
Translocation is the movement of food substances (mainly sucrose) through Phloem Tissue.
142
Which strengthening material is present in the walls of Xylem Tubes?
(1 mark)
Lignin
143
Which type of transport vessel is made up of dead cells?
| 1 mark
Xylem
144
How are Root Hair Cells adapted for the uptake of Water and Mineral Ions?
(1 mark)
They have a large surface area.
145
What is the role of Xylem Tubes in a Plant?
| 5 marks
Xylem Tubes carry water and mineral Ions from the roots to the stem and the leaves.
146
How does the structure of Phloem allow food substances to move between Phloem Cells?
(3 marks)
There are pores in the end walls of Phloem Cells for the food substances to move through.
147
Describe the movement of food substances, via Phloem Tubes, in plants.
(6 marks)
Food substances move through Phloem Tubes in both directions. The food substances move from the leaves, where they are made, to the rest of the plant.
148
Explain the constant transpiration stream of water through a Plant.
(9 marks)
Evaporation and diffusion of water from the leaves create a short storage of water in the leaf. This means more water is drawn up from the rest of the plant through the Xylem Vessels to replace it. This causes more water to be drawn up from the roots.
149
What part of the plant transports food in both directions in translocation?
(1 mark)
Phloem
150
What controls the opening and closing of the Stomata?
| 6 marks
Guard Cells (they open Stomata when Turgid and close Stomata when Flaccid).
151
Give 3 Factors that can Affect the Rate of Transpiration.
| 3 marks
Light intensity, temperature and air flow.
152
A student estimated the Rate of Transpiration in a Plant by measuring the Rate of Water Uptake. 2cm^3 of Water was taken up by the plant in 15 minutes.
Calculate the Rate of Water Uptake in cm^3/hour.
(9 marks)
60 minutes / 15 minutes = 4
| So the rate = 2cm^3 x 4 = 8cm^3/hour.
153
Why is the rate of Transpiration very low at night time?
| 7 marks
Photosynthesis can’t happen in the dark, so Stomata don’t need to be open to let Carbon Dioxide inside the leaf.
This means Stomata begin to close as it gets darker, which reduces the amount of water able to escape from leaves.
154
Simple Explain Transpiration and Why Plants Do It
| 7 marks
The release of water from plant leaves, to cool the plant or pumping water and minerals to the leaves for photosynthesis.
155
A table shows the Rate of Water Uptake of 2 Plants, X and Y. The plants are in identical rooms, except 1 room contains a fan next to the plant.
X’s Rate of Uptake - 10.1 cm^3
Y’s Rate of Uptake - 3.2cm^3
Suggest which plant, X or Y, is next to the fan.
Explain your answer.
(10 marks)
Plant X must be next to the fan as it has a higher rate of Water Uptake than Plant Y. The movement of air from the fan sweeps away water vapour, maintaining a low concentration of water outside the leaves of Plant X and increasing the rate of which water is lost through diffusion - this means that the rate of transpiration will be higher.
156
How might increasing the temperature in a room affect the rate of Water Uptake in 2 plants?
(6 marks)
Increasing the temperature would increase the rate of transpiration because the water particles would have more energy to evaporate and diffuse out of the Stomata.
157
What can be used to estimate the Rate of Transpiration?
| 5 marks
A Potometer - by measuring the distance a bubble moved along a Capillary tube in a certain length of time.
158
How are hormones transported around the body?
| 1 mark
In the blood.
159
True or False? Only Females have Ovaries.
| 3 marks
True. Males do not have Ovaries (they have Testes instead).
160
Where is the Pancreas located in the human body?
| 2 marks
Behind the Stomach.
161
Where is the Thyroid (Gland) found in the human body?
| 2 marks
In the front of the neck.
162
Where is the Adrenal Gland found in the human body?
| 2 marks
Above the Kidney.
163
Which Gland produces hormones that act on other glands?
| 1 mark
The Pituitary Gland.
164
What is a target organ?
| 2 marks
A target organ is the particular organ that a hormone affects.
165
Describe the role of the Testes in males.
| 3 marks
The testes produce testosterone, which controls puberty and Sperm production.
166
What glands is the Endocrine system made up of?
| 10 marks
- Pineal Gland
- Pituitary Gland
- Thyroid
- Thymus
- Adrenal Gland
- Pancreas
- Ovary
- Testis/Testicles (plural: Testes)
167
Where is the Pineal Gland found in the human body?
| 3 marks
Deep in centre of the Brain where both sides join.
168
Where is the Pituitary Gland found in the human body?
| 3 marks
Base of your Brain behind your nose and between your ears.
169
Where is the Thymus found in the human body?
| 2 marks
In the chest between the Lungs.
170
Where are the Ovaries found in the human body?
| 4 marks
In the Pelvis; between hips, in the lower part of the tummy.
171
Where is the Testis found in the human body?
| 2 marks
Inside the Scrotum.
172
What is the role of the Ovaries?
| 7 marks
Produce Egg Cells (called Ova or Oocytes) which are transported to the Fallopian Tube where Fertilisation by a Sperm may occur.
173
Describe the role of the Pancreas.
| 7 marks
Makes Pancreatic juices (Enzymes), which break down sugars, fats and starches. Your Pancreas also makes hormones helping out your Digestive System.
174
Describe the role of the Adrenal Gland.
| 7 marks
Also known as Superarenal Glands produce hormones that help regulate your Metabolism, Immune System, Blood Pressure, Response to stress and other essential functions.
175
What is the job of the Thyroid?
| 8 marks
Produces hormones that control the speed of your metabolism (system that helps the body use energy). Thyroid disorders can slow down or rev up metabolism by disrupting the production of thyroid hormones.
176
Name the Gland that produces Adrenaline.
| 1 mark
Adrenaline is produced by the Adrenal Glands.
177
What is metabolic rate?
| 2 marks
The speed at which Chemical Reactions happen in the Body.
178
Owen has hypothyroidism, a Disease which affects the activity of his Thyroid. As a result, he has a low Metabolic Rate. Suggest whether Owen has an Overactive Thyroid or an Underactive Thyroid.
(4 marks)
Owen has an Underactive Thyroid. Not enough Thyroxine is being released from the Thyroid to stimulate his Metabolic Rate.
179
Chernice is frightened of spiders. She finds a big spider in her bath and her heart rate starts to race.
Explain Chernice’s response.
(13 marks)
Chernice’s Brain detects her fear and sends Nervous Impulses to her Adrenal Glands, which respond by secreting Adrenaline. This increases her Heart Rate and Blood Pressure to help increase the Blood flow to her Muscles. This increases the supply of Oxygen and Glucose to the Cells for increased Respiration, which prepares her for the ‘fight or flight’ response.
180
A diagram shows how the level of Thyroxine in the Blood changes over time.
Explain what happens in the Body when Blood Thyroxine levels are low.
(13 marks)
The level of Thyroxine, when lower than normal, stimulates the release of Thyrotropin Releasing Hormone (TRH) from the Hypothalamus.
TRH stimulates the Pituitary Gland to release Thyroid Stimulating Hormone (TSH).
This increases the amount of Thyroxine released from the Thyroid Gland so that the level in the Blood increases back to normal. This is Negative Feedback.
181
What automatic (subconscious) response keeps things in your body at the right level?
(1 mark)
Negative Feedback
182
What is the term used to describe the release of an Egg from an Ovary?
(1 mark)
Ovulation
183
Name the hormone that maintains the lining of the Uterus.
| 1 mark
Progesterone
184
Describe how the lining of the Uterus changes over the stages of the Menstrual Cycle.
(17 marks)
- During stage 1 of the Menstrual Cycle the Uterus Lining breaks down.
- During stage 2 the Lining of the Uterus builds up again into a thick layer full of Blood Vessels.
- The Lining of the Uterus is then maintained during stages 3 and 4.
- If no Fertilised Egg implants in the Uterus Wall by Day 28, the Uterus Lining starts to break down, and a New Cycle begins at Stage 1.
185
Describe how hormones control the development and release of an Egg.
(11 marks)
FSH (Follicle-Stimulating Hormone) causes an Egg to mature in a follicle in one of the Ovaries.
LH (Luteinising Hormone) then stimulates the release of a Matured Egg at Day 14 (Ovulation)
186
Explain the role of Oestrogen between Days 4 - 14 of the Menstrual Cycle.
(6 marks)
This hormone causes the Lining of the Uterus to grow between days 4 - 14.
Towards day 14, it stimulates the release of LH (which stimulates the release of an Egg).
187
What Hormones are Used During Menstruation? (In order)
| 6 marks
- Follicle-Stimulating Hormone (FSH)
- Luteinising Hormone (LH)
- Oestrogen
- Progesterone
188
What is the job of the Oestrogen and Progesterone during Menstruation?
Oestrogen and Progesterone stimulate the uterus and breasts to prepare for possible fertilization.
Progesterone maintains the Uterus Lining.
189
List the phases of the menstrual cycle.
| 6 marks
Follicular (before release of the egg)
Ovulatory (egg release)
Luteal (after egg release)
190
Which Hormone causes the level of Oestrogen (primary female hormone) to rise?
(2 marks)
Follicle-Stimulating Hormone (FSH)
191
Describe the role of the Leutinizing hormone (LH).
| 5 marks
Reproductive pituitary hormone, aids in egg maturation and provides the hormonal trigger to cause ovulation and the release of eggs from the ovary.
192
Describe the role of the Follicle-Stimulating Hormone (FSH).
| 3 marks
Responsible for starting follicle (egg) development and causing the level of Oestrogen to rise.
193
During the Menstrual Cycle, when is Oestrogen low?
| 6 marks
End of Cycle until Mid- Follicular Phase when it rises. It then drops after Ovulation until Mid-Luteal Phase when it rises again.
194
When does Oestrogen rise during the Menstrual Cycle?
| 3 marks
Mid-Follicular Phase (Ovulation) and during the Mid-Luteal Phase.
195
When is Progesterone low during the Menstrual Cycle?
| 3 marks
During Menstruation and Post-Menstruation (early Follicular Phase)
196
When are Progesterone levels high during the Menstrual Cycle?
(6 marks)
During the Luteal Phase, it the takes a slight dip but is still high during the Mid-Luteal Phase. It then rises again Pre-Menstruation.
197
When is the Luteinising Hormone at its peak during the Menstrual Cycle?
(2 marks)
During the Follicular Phase.
198
When is the Luteinising Hormone low during the Menstrual Cycle?
(4 marks)
During the Luteal, Pre-Menstrual and Menstrual Phases.
199
When is the Follicle-Stimulating Hormone (FSH) at its highest during the Menstrual Cycle?
(2 marks)
During the Follicular Phase.
200
When is the Follicle-Stimulating Hormone low during the Menstrual Cycle?
(7 marks)
During Menstruation, early Follicular Phase, it dips at Luteal Phase and rises slightly Pre-Menstruation.
201
When do the levels of FSH and LH in the blood increase?
| 5 marks
During Puberty - the Eggs begin to mature and a collection of fluid (the follicle) begins to develop around each one.
202
During what days of the Cycle does the Menstruation take place?
(2 marks)
Days 1-7
203
During what days of the Cycle does the Follicular Phase take place?
(2 marks)
Days 7 - 14
204
During what days of the Cycle does the Luteal Phase take place?
(3 marks)
Days 14 - 21
205
During what days of the Cycle does the Pre-Menstrual Phase take place?
(2 marks)
Days 21 - 28
206
What does the Follicular Stage consists of?
List days and different phases.
(9 marks)
Days 1 - 7 Menstrual Phase
Day 7 Mid-Follicular Stage
Days 7/8 - 14 Follicular Phase
207
What does the Periovulatory Stage consists of?
List days and different phases.
(4 marks)
Days 13 - 15
| End of Follicular and Luteal Phases
208
What does the Luteal Stage consists of?
List days and different phases.
(11 marks)
Days 14/15 - 21 Luteal Phase
Days 20 - 22 Mid-Luteal Phase
Days 21/22 - 28 Pre-Menstrual Phase
209
Match to (Menstrual Cycle) hormones;
(mU/mL)
(2 marks)
Luteinising Hormone and Follicle-Stimulating Hormone.
210
Match to (Menstrual Cycle) hormones;
(ng/mL)
(2 marks)
Oestrogen and Progesterone.
211
During Ovulation;
When the level of Oestrogen is sufficiently high, what is produced? And when?
(2 marks)
Luteinising Hormone - Day 14 of the Cycle.
212
28 - 36 hours after what does Ovulation take place?
| 4 marks
After the onset of the LH surge and 10 to 12 hours after LH reaches its peak.
213
What is the Corpus Luteum?
| 8 marks
After Ovulation when left behind Cells in the Ovarian Follicle undergo a transformation.
It produces Oestrogen and high amounts of Progesterone to prepare the lining of the Uterus for implantation.
214
What happens during the Luteal Phase if Pregnancy occurs?
| 9 marks
Corpus Luteum support the fertilized egg, the Embryo, with its production of progesterone (responsible for changes that occur during Fertilisation to support the Egg)
Progesterone influences the Uterus into creating a highly vascularized bed for the Egg.
215
If pregnancy occurs how long does the Corpus Luteum produce Progesterone for?
(2 marks)
Until about 10 weeks gestation.
216
If no embryo implants, what happens to the Corpus Luteum’s Progesterone production?
(7 marks)
The circulating levels of hormone decline with the degeneration of the Corpus Luteum and the shedding of the Uterus Lining (Endometrium), leading to bleeding.
