Unit 1 Flashcards
(201 cards)
1
Q
What are is the function of carbohydrates?
A
To release energy.
2
Q
What are is the function of proteins?
A
To grow, repair and replace cells.
3
Q
What are is the function of fibre?
A
To make sure everything runs smoothly in the digestive system.
4
Q
What are is the function of fats?
A
To keep warm and release energy.
5
Q
What are is the function of vitamins and minerals?
A
To maintain general health of bones, skin, teeth and blood.
6
Q
What is a metabolic rate?
A
The rate at which chemical reactions occur in the body.
7
Q
What affects resting metabolic rate?
A
Muscle to fat ratio. The higher it is, the faster the metabolic rate.
8
Q
What can eating too much lead to?
A
Obesity.
9
Q
What is considered obesity?
A
Being 20% over recommended body mass.
10
Q
What health issues can arise from obesity?
A
Arthritis, high blood pressure, heart disease.
11
Q
What increases blood cholesterol?
A
Eating too much saturated fat.
12
Q
What does eating too much salt cause?
A
High blood pressure and heart problems.
13
Q
What does eating too little do?
A
Malnutrition.
14
Q
What are the effects of malnutrition?
A
Slow growth, fatigue, poor resistance to infection, irregular periods in women.
15
Q
What does exercise do to the body?
A
Decreases the amount of energy stored as fat.
16
Q
Which inherited factor reduces the metabolic rate?
A
Underactive thyroid gland.
17
Q
What is cholesterol?
A
A fatty substance found in every cell imperative for good health.
18
Q
What does increased cholesterol do?
A
Increase risk of heart disease.
19
Q
What are the two main types of pathogen?
A
Bacteria and Virus
20
Q
What is a bacteria?
A
A very small cell which can reproduce rapidly in the body.
21
Q
How do bacteria make you feel ill?
A
Damaging cells
Producing toxins.
22
Q
What is a virus?
A
Viruses are not cells and are 1/100th the size of a bacteria.
23
Q
How do viruses make you feel ill?
A
Replicate themselves using mechanics inside of normal cells and bursting the cells to release replicas. The damage makes you feel ill.
24
Q
What stops pathogens getting into the body?
A
Skin, hairs and mucus.
25
What are the job of platelets?
To clot the blood.
26
What is the main part of the immune system?
White blood cells.
27
What are the three roles of the white blood cells?
Consuming foreign cells.
Producing antibodies.
Producing antitoxins.
28
What is the process of producing antibodies?
Each invading cell has unique antigens on its surface. The white blood cells recognise this and produce antibodies. These then lock onto the antigens and kill the invading cell. The next time the body is infected by the same cells, the white blood cells know which antibodies to produce and they kill the cells.
29
What are the pros and cons of vaccination?
Advantages:
Help control disease.
Prevent epidemics.
Disadvantages:
Don't always work
People can have bad reactions.
30
What do painkillers do?
Relieve symptoms but not cure the illness.
31
What do antibiotics do?
Kill bacteria without killing body cells.
32
What don't antibiotics destroy?
Viruses.
33
Why are viruses difficult to destroy?
They take over body cells so they are hard to destroy without killing body cells.
34
What is antibiotic resistance?
Being able to not be killed by antibiotics.
35
How do bacteria become antibiotic resistance?
Some bacteria survive a wave of antibiotics and reproduce to form a colony of antibiotic resistant bacteria. The next time the person takes antibiotics, the resistant ones survive and the rest die; an example of natural selection.
36
What causes antibiotic resistance?
Over prescribing antibiotics.
37
How are microorganisms cultured?
Hot agar is poured into a petri dish.
An innoculating loop is burned to sterilise.
The microorganisms are transfered when everrything has cooled to agar jelly.
A lid is placed on top to stop microorganisms in the air contaminating.
38
Why can't microorganisms be grown higher than 25°C in school?
Harmful pathogens can't grow at temperatures lower than it.
39
What did Semmelweis discover?
Women were dying after childbirth as the doctors looked after them after dealing with dead bodies.
40
What is Semmelweis insist his doctors did?
Wash their hands in antiseptic solution.
41
Why were Semmelweis' ideas not excepted straight away?
There was no knowledge about bacteria.
42
What is MRSA?
An antibiotic resistant bacteria.
43
What are the issues with bacteria?
Bacteria can mutate.
Bacteria an become antibiotic resistant.
When bacteria mutates, no one is immune to the new strain.
Mutated bacteria can cause an epidemic.
44
What are the issues with viruses?
Viruses mutate often so they are hard to produce vaccinations against them as their antigens kepp changing.
If viruses become very infectious, it is hard to control the spread as so many people use planes.
Pandemics can kill billions of people.
45
What is a stimulus?
A change in your environment that you my need to react to.
46
What are the five sense organs?
Eyes, ears, nose, mouth, skin.
47
What do the sense organs contain?
Receptors.
48
What are receptors?
Groups of cells that are sensitive to a stimulus. They change stimulus energy (light energy) into electrical energy.
49
Examples of stimulus.
Light, sound, touch, pressure, pain, chemical, change in position, change in temperature.
50
What receptors are in the eyes?
Light receptors.
| They contain a nucleus, cytoplasm and cell membrane.
51
What receptors are in the ears?
Sound and balance.
52
What are balance receptors sensitive to?
Change in position.
53
What receptors are in the nose?
Smell stimuli.
54
What receptors are in the tongue?
Taste receptors.
55
What are taste receptors sensitive to?
Bitter, sweet, salt, sour, savoury.
56
What is the skin sensitive to?
Touch, pressure, pain and change in temperature.
57
What are the three neurones?
Relay, sensory and motor.
58
Where do the sensory neurones take impulses from and to?
From receptors to the central nervous system.
59
Where do relay neurones take impulses from and to?
From sensory neurones to motor neurones.
60
Where do the motor neurones take impulses from and to?
From the central nervous system to the effector.
61
What are effectors?
Muscles and glands that respond to impulses from the nervous system. Muscles contract, gland secrete hormones.
62
What is the central nervous system?
The place where impulses are sent from the sense organs and where responses are coordinated.
63
How are impulses sent?
As electrical impulses.
64
Where are "instructions" from the central nervous system sent?
To the effectors.
65
What is a synapse?
The connection between two neurones.
66
How is a signal transferred across a synapse?
By chemicals which diffuse across the gap.
67
What are reflexes?
Automatic responses to certain stimuli which decrease the chance of injury.
68
What is an example a reflex?
The pupils automatically getting smaller when a bright light is shined into the to stop the eye getting damaged.
69
What is the name of the passage of information in a reflex?
A reflex arc.
70
Example reflex arc.
Stimulus - Receptor - Sensory- Relay- Motor-Effect-Response
71
What are hormones?
Chemical messengers which travel in the blood to activate target cells.
72
What part of the blood are hormones carried in?
Plasma.
73
What do hormones affect?
Target cells.
74
What do hormones mostly control?
Things in organs that need constant adjustment.
75
Where are hormones produced and secreted?
Glands.
76
How are the effects of a hormone described?
Long-term.
77
What hormones does the pituitary gland secrete?
FSH and LH.
78
What hormone does the ovaries secrete?
Oestrogen.
79
Hormones vs Nerves : Nerves.
Very fast
Short term
Precise area.
80
Hormones vs Nerves : Hormones.
Slower
Long-term
General area.
81
Stage 1 of menstrual cycle.
Break down of the uterus. (4 days)
82
Stage 2 of menstrual cycle.
Uterus builds up into spongy layer full of blood vessels ready for fertilised egg. (10 days)
83
Stage 3 of menstrual cycle.
Release of egg. (1 day)
84
Stage 4 of menstrual cycle.
Wall is maintained. If no egg is fertilised, the cycle starts again.
85
What is the job of FSH?
Causes an egg to mature in one of the ovaries.
| Stimulates ovaries to produce oestrogen.
86
What is the job of Oestrogen?
Cause pituitary gland to produce LH.
| Inhibits release of FSH.
87
What is the job of LH?
Stimulate release of egg in the middle of the menstrual cycle.
88
What does FSH stand for?
Follicle-Stimulating Hormone.
89
What does LH stand for?
Luteinising Hormone.
90
Where is progesterone produced?
In the ovaries.
91
How oestrogen be used to reduce fertility?
High levels in the body prevent FSH being produced so no eggs are matured.
92
How does progesterone reduce fertility?
Stimulates the production of a thick cervical mucus which prevents any sperm reaching an egg.
93
Pros of the pill.
Over 99% effective.
| Reduces risk of certain cancers.
94
Cons of the pill.
Isn't 100% effective.
Can cause side effects.
Doesn't protect against STDs.
95
What side effects can be caused from the pill?
Headaches, nausea, irregular bleeding and fluid retention.
96
What are the benefits of injecting LH and FSH into the body?
It can help women who couldn't get pregnant, get pregnant.
97
What are the drawbacks of injecting LH and FSH into the body?
It doesn't always work.
Women may have to do it many times which is expensive.
Too many eggs can be stimulated causing multiple births. (twins, triplets).
98
What does IVF stand for?
In Vitro Fertilisation.
99
Explain IVF treatment.
Eggs are colllected from ovaries and fertilised using male's sperm.
Fertilised eggs grow into embryos.
One or two are transferred to the woman's uterus.
100
Why is FSH and LH given to the woman before egg collection?
To stimulate egg production so more eggs can be taken.
101
What are the pros of IVF?
Infertile couples can have children.
102
What are the drawbacks of IVF?
Some women have strong reactions to the hormone treatment. (abdominal pain, vomiting, dehydration))
May have increased chance of caner.
Multiple births.
103
What is auxin?
A plant growth hormone.
104
Where is auxin produced?
At the tips of roots and shoots.
105
What does auxin do?
Moves backwards to stimulate cell elongation.
106
What effect does auxin have in the roots?
It inhibits growth.
107
What effect does auxin have in the shoots?
It stimulates growth.
108
What three factors affect auxin?
Light (phototropism)
| Gravity (geotropism)
109
Explain phototropism.
When light is shined on the shoot, the auxin move away from the light causing the cells on the shaded side to grow faster, causing the shoot to bend towards the light.
110
Explain geotropism in shoots.
When a shoot is lying on its side, the auxin move to the lower side, causing it to grow faster making the shoot bend away from the force of gravity (upwards).
111
Explain geotropism in roots.
The auxin move to the lower side causing it to grow more slowly. Therefore the upper side grows faster and the root bends downwards towards gravity.
112
Explain the effects of moisture on auxin in the roots.
The auxin will move to the side with more moisture, slowing the growth down. Therefore the other side will grow faster causing the root to bend towards the moisture.
113
How does weedkiller work?
Plant growth hormones affecting broad-leaved plants are sprayed onto weeds, causing them to grow rapidly which kills them.
114
What causes roots to grow from plant cutting?
Auxin in rooting compound.
115
What is homeeostasis?
The control of functions in the body to maintain a "constant internal environment".
116
What needs to be kept constant in the body?
Ion content.
Water content.
Blood sugar levels.
Temperature.
117
How are ions taken into the body?
In food.
118
How are excess ions removed from the body?
Sweat and removal via the kidneys.
119
How is water taken into the body?
Food and drink.
120
How is water lost in the body?
Sweat.
Breathing
Urine.
121
Describe water loss on a cold day or when not exercising.
Less sweat.
More urine.
Dilute urine.
122
Describe water loss on a hot day or when exercising.
More sweat.
Less urine.
Concentrated urine.
123
How is body temperature controlled?
The brain controls body temperature by receiving messages from skin and being sensitive to blood temperature.
124
What temperature to enzymes in the body work best at?
37°C.
125
Where does the body get glucose from?
Food such as carbohydrates.
126
What hormone controls blood sugar levels?
Insulin.
127
When is more glucose used in the body?
During exercise.
128
What is a drug?
A substance which alters the body chemistry.
129
What are the three type of drugs?
Medicinal, Recreational or Performancing Enhancing.
130
What are medicinal drugs?
Drugs that are used for medical purposes such as antibiotics.
131
What are the two types of medicinal drugs?
Prescription and behind the counter.
132
What are recreational drugs?
Drugs used for fun. These can be illegal or legal.
133
What are performance enhancing drugs?
Drugs that improve the performance of a person in sport.
134
What are the two types of performance enhancing drugs?
Anabolic steroids and stimulants.
135
What do anabolic steroids do?
Increase muscle size.
136
What do stimulants do?
Increase heart rate.
137
What negative effects are linked to steroids?
High blood pressure.
138
Why are some people for drugs in sport?
Athletes have the right to make their own decision.
| Sport is fair anyway as different athletes have access to different coaches, facilities and equipment.
139
Why are some people against drugs in sport?
It unfair if people gain an advantage by taking drugs and not just through training.
Athletes may not be informed of the serious health risks.
140
What are statins?
Prescribed drugs used to lower risk of heart and circulatory disease.
141
What did the research show about statins?
It lowers blood cholesterol and significantly lowers the risk of heart disease in diabetic patients.
142
What claims are there about cannabis?
That is leads to mental illness.
143
What is the first stage of drug testing?
Testing on human cells and tissues.
144
What is the second stage of drug testing?
Live animals to test toxicity and the best dosage.
145
What is the third stage of drug testing?
Clinical trials on healthy volunteers to test for side effects.
146
What is the fourth stage of drug testing?
Ill volunteers in blind/ double blind trials.
The volunteers are split into two groups, one group given drug, one given placebo. Neither doctor or patients know who has the drug or placebo so there is no bias.
147
Why is a placebo used in clinical trials?
So the doctor can actually see what effect the drug has.
148
What was the issue with thalidomide.
Thalidomide was tested as a sleeping pill however was found to treat morning sickness. No-one tested the effects on pregnant women or unborn babies so babies were born with deformed limbs.
149
What is thalidomide now used to treat?
Leprosy and other diseases (some cancers).
150
What two classes are illegal drugs divided into?
Hard and soft.
151
Why do people use hard drugs?
Enjoyment, relaxation, stress relief, inspiration.
152
What do some people say cannabis is?
A gateway drug and stepping stone drug.
153
"Cannabis is a stepping stone drug". Explain.
It can lead to the user wanting to take harder substances.
154
"Cannabis is a gateway drug". Explain.
Cannabis brings people into contact with drug dealers.
155
What are the genetics behind cannabis and harder drugs?
Certain people are more likely to take drugs generally so cannabis users will also try other drugs.
156
What effects does smoking have?
Causes heart, blood vessel and lung disease.
Tobacco smoke causes cancer.
Nicotine is very addictive.
157
What effects does alcohol have?
Affects nervous system and slows down the body's reactions.
Impaired judgement, poor coordination and unconsciousness.
Liver disease and brain damage
Addiction.
158
Why do smoking and alcohol have a bigger impact on society than illegal drugs?
More people take them.
159
How have desert animals adapted?
Large surface area compared to volume.
Efficient with water.
Good in hot conditions.
Camouflage.
160
How does a large surface area compared to volume help desert animals to survive?
Lose more body heat.
161
How does water efficiency help desert animals to survive?
They lose less water by having more concentrated urine.
162
How does being good in hot conditions help desert animals to survive?
They have thin layers of body fat and thin coats to lose more body heat.
163
How does camouflage help desert animals to survive?
A sandy colour makes them difficult to see so they can avoid predators or sneak up on prey.
164
How have arctic animals adapted to reduce heat loss?
Small surface area compared to volume.
Well Insulated.
Camouflage.
165
How does a small surface area compared to volume help arctic animals to survive?
Small surface area reduces heat loss.
166
How does being well insulated help arctic animals to survive?
They have a thick layer of blubber for insulation (also an energy supply when food is scarce).
Thick coats to keeps body heat in and grease sheds water to prevent evaporation.
167
How does camouflage help arctic animals to survive?
A white colour makes them difficult to see so they can avoid predators or sneak up on prey.
168
How have desert plants adapted to having little water?
Small surface area compared to volume.
Water Storage Tissues
Maximising water absorption.
169
How does a small surface area compared to volume help desert plants survive with little water?
Less water vapour can be lost from the surface.
| Cacti have spines instead of leaves so water cannot be lost by evaporation.
170
How does having water storage tissue help plants survive with little water?
Cacti, for example, can store water in its stem.
171
How does maximising water absorption help plants survive with little water?
Some plants have deep roots to absorb water further away.
172
How are plants and animals adapted to deter predators?
Armour.
Poisons.
Warning Colours.
173
What are extremophiles?
Microorganisms that have adapted to live in seriously extreme conditions like volcanoes, salty lakes or high pressures beneath the sea.
174
What do plants need in order to survive?
Light, space, water, minerals (nutrients).
175
What do animals need to survive?
Space (territory), food, water, mates.
176
Why is the population of red squirrels decreasing?
They are unable to compete for resources against grey squirrels.
177
What are the living factors that cause environmental change?
```
Infectious disease.
Increase/Decrease of predators.
Increase/Decrease of prey.
Increase/Decrease of food sources.
Increase/Decrease in the number of competitors.
```
178
What are the non-living factors that cause environmental change?
Increase/Decrease in average temperature.
Increase/Decrease in average rainfall.
Increase/Decrease in level of air or water pollution.
179
What happens to a population is the number of prey increases?
It increases.
180
What are the reasons for a decrease in population size?
Less food.
More disease.
More pesticides (insects).
181
What causes a change in distribution of a population?
A change in temperature.
182
What name is given to species that are sensitive to change in their environment?
Indicator species.
183
What indicator species is used to monitor air pollution?
Lichen.
184
How does lichen monitor air pollution?
Depending on the type of lichen in an area, the different levels of sulphur dioxide from car exhausts and power stations ect... there is.
185
What indicates oxygen rich, clean river water?
Mayfly larvae.
186
How does mayfly larvae indicate clean water?
If raw sewage is released into a river, the bacteria population increases and uses up all of the oxygen. Mayfly larvae are sensitive to the change in oxygen levels. If there is mayfly larvae, then the water is clean.
187
What species indicate high levels of water pollution?
Sludge worm and rat-tailed maggots.
188
What do satellites measure?
The temperature of the sea surface and the amount of snow and ice cover.
189
What do automatic weather stations measure?
The atmospheric temperature.
190
What do rainfall gauges measure?
Rainfall.
191
What measures the concentration of dissolved oxygen in water?
Dissolved oxygen meters.
192
What happens as you move up a trophic level in a food chain?
Energy and biomass decreases.
193
What does each bar in a pyramid of biomass represent?
The amount of biomass.
194
Where does some of the energy from the sun go?
Into green plants and algae during photosynthesis.
195
Where does some of the energy from plants go?
To animals when the plants are eaten.
196
How is energy lost from the food chain in animals?
Through the movement of the animals, heat loss and inedible biomass such as bones.
197
Why are the hardly any food chains with five or more strophic levels?
Too much energy is lost to support organisms at that stage.
198
What happens to elements in the food chain?
to the start of the food chain bay decay.
199
What microorganisms decay?
Decomposers.
200
What conditions are best for decay?
Warm, moist conditions with lots of oxygen.
201
How is carbon taken from the atmosphere?
Photosynthesis.
