Biology Flashcards
0
Q
Nucleus:
A
Controls the cell. It contains information needed to produce a new living organism.
1
Q
What are the 7 characteristics of all living things?
A
Movement Respiration Sensitivity Growth Reproduction Excretion Nutrition
2
Q
Cytoplasm:
A
Liquid where chemical reactions take place.
3
Q
Cell membrane:
A
Holds the cell together and controls what passes in an out of the cell.
4
Q
Cell wall (plant cell):
A
Made of cellulose which gives a plant strength and support.
5
Q
Vacuole (plant cell):
A
Contains a weak solution of salt and sugar called cell sap.
6
Q
Chloroplasts (plant cell):
A
Contains a green substance called chlorophyll which absorbs the suns energy for photosynthesis.
7
Q
Cell division - what is the process of cells multiplying into exact copies?
A
Mitosis
Meiosis occurs when producing sex cells
8
Q
What is a tissue?
A
A group of similar cells working together.
9
Q
What’s an organ?
A
An organ is made up of different tissues working together.
10
Q
How are organ systems made?
A
Through cells, tissues and organs, all of these cells make up an organ system.
11
Q
What are special cells?
A
They can change shape to carry out another cell’s job.
12
Q
Special animal cells
Red blood
Sperm
Nerve
A
It has a tail to move
They can carry oxygen around the body
Shaped like wires to send messages around the body.
13
Q
Special plant cells
Palisade
Root
A
Have a lot of chloroplasts
Root hair is long and thin to absorb water and minerals from the soil.
14
Q
Organ systems
Name at least 5:
A
Skeletal Muscle Respiratory Digestive Circulatory Reproductive Excretory Nervous Endocrine
15
Q
What is diabetes?
A
When the pancreas isn’t making enough hormone insulin. The insulin makes sure your body has enough glucose.
16
Q
What are the organs in the excretory system?
A
Kidneys and the bladder
17
Q
What are phloem tubes?
A
They carry glucose made by leaves
18
Q
What do carbohydrates do?
A
Give us energy
19
Q
Chemical test for starch:
A
Iodine solution
20
Q
Test for glucose:
A
Benedict’s solution:
21
Q
Why do we need protein?
A
Repair and replace cells
22
Q
Energy depends on…
A
Someone’s…
Size
Age
Activity
23
Q
Test for protein:
A
Biuret test
24
What are enzymes?
There are 3
Protease
Amylase
Lipase
They break up the molecules so they are small enough to be absorbed.
25
What is a villi?
During absorption in the small intestine, they extend from the wall.
26
What is the difference between arteries and veins?
Arteries are thicker and carry oxygenated blood.
Veins are thinner and carry deoxygenated blood.
27
What are the for chambers of the heart?
L and R atria
| L and R ventricle
28
What is a capillary?
One cell thick.
They have very thin walls to allow oxygen and nutrients to diffuse out of them.
Small branches between an artery and a vein which exchanges substances.
29
Which blood vessels carry blood away from the heart?
Arteries
30
Which side of the heart receives deoxygenated blood.
Right
31
What do white blood cells do?
Protects us against diseases
32
What do red blood cells do?
They carry oxygen to the cells in the body. They carry haemoglobin and have no nucleus. They are small enough to fit through capillaries.
33
What does plasma do?
Carry substances around the body.
34
Where are joints?
Where 2 bones meet.
35
What is the skeleton for?
Support
Protection
Movement
36
What's the movement of air called?
Ventilation
37
What is respiration?
It is NOT breathing in and out. It's a chemical reaction that breaks down glucose from food to release energy using oxygen
38
What is an alveoli?
It's where gas exchange occurs (veins carry blood to the alveoli and as it travels around the air-sack,it picks up oxygen)
39
What is a microbe?
A microorganism especially a bacterium, which causes fermentation.
40
4 main types of microbe:
Protozoa
Bacteria
Fungi
Virus
41
What is a virus gene like?
Protein coat
Genetic material
3 tail shape
42
2 ways for white blood cells to kill microbes:
Engulf the bacteria or antibodies fight them.
43
What is natural immunity?
When you have caught the disease once before and still have antibodies in your body, your body is prepared for the disease.
44
What is artificial immunity?
It involves the use of vaccines. (A vaccine contains dead or harmless microbes.) your white blood cells still react to these microbes and antibodies are produced. You would then be immune
45
Carpel (female) parts of a flower...
Stigma
Style
Ovary
46
Stamen (male) parts of a flower...
Petal
Anther
Filament
Sepal
47
What is self and cross pollination.
Self is when insects or the wind carries pollen from the anther to the stigma.
Cross is when insects or the wind carries pollen from the anther of one plant to the stigma of another.
48
What's classification?
It's how scientists group different living organisms. There are 2 main areas. The animal kingdom and the plant kingdom.
49
What is a vertebrates
Animals with a backbone (spine)
| Invertebrates don't have a spine
50
What are the vertebrates of the animal kingdom?
```
Fish - live in water
Amphibians - live on water and land
Mammals - have hair on their bodies
Reptiles - dry and scaly
Birds - feathers and wings. Lay eggs.
```
51
What are keys (in classification):
A way to identify a certain type of animal e.g.
Has it got legs
Has it got wings Has it got a shell
E.t.c.
52
Is someone's blood group inherited or due to the environment?
Inherited
53
What are the food groups?
| 7
```
Carbohydrates
Proteins
Fats
Minerals
Vitamins
Water
Fibre
```
54
What's a balanced diet?
It is a diet which provides you with the correct amount of food from all food groups.
55
What do carbohydrates provide you with?
Slow release (initial source of) energy.
56
What do proteins provide you with?
Growth and repair of cells.
| Healing.
57
What do fats provide you with?
```
Stored energy (often stored around organs)
Insulation
```
58
What do vitamins provide you with?
Cell production.
59
What do minerals provide you with?
Cell production.
60
What's the equation to work out BMI?
| Body Mass Index
BMI = weight (kg) / height (m squared)
61
What are the three types of sugar and what are they found in?
Sucrose - in foods e.g. tea
Lactose - in milk
Glucose - in our bodies
62
What are fat molecules made up of?
A glycerol molecule and 3 fatty acid molecules.
63
What are the 2 types of fat?
Saturated fats from animals
| Unsaturated fats from plants
64
What is cholesterol
A chemical made in the liver and found in the blood, amounts of which depend on our diet. High levels lead to heart diseases and high blood pressure.
65
How do you become obese?
If your energy intake is higher than your energy out-take.
66
Can fibre be digested?
No
67
What do enzymes do?
Break up molecules within the body
68
What is a pathogen / microbe?
An organism that causes diseases
69
4 main types of pathogen / microbe:
Virus
Bacteria
Fungi
Protozoa
70
How do pathogens cause illness?
By toxins, reproduction or immune response.
71
What are the steps to prepare an agar plate?
1. Wash your hand and the surrounding objects and areas / surfaces.
2. Pass the neck of the bottle containing the agar jelly through a flame to kill any microbes.
3. Take a sterile dish and pour the jelly in and leave it to set.
4. Take a sterilised loop of metal or sterilised pipette (sterilised by either flame, vacuum or cleaning).
5. Take a sample of the microbe using the metal loop or pipette.
6. Lift the lid, at a slight 45* angle to not allow any other microbes in, and put the microbe sample onto the set agar plate.
7. Put the lid back onto the plate and seal it.
8. Label the dish, put a safety hazard sign on it and put it somewhere to allow it to grow.
9. When done, wash hands and surfaces.
72
What is MRSA?
It stands for methicillin resistant staphylococcus aureus.
It is a bacteria which can mutate and cannot be cured by antibiotics.
It spreads very easily and, despite living on our skin safely, can kill.
It can't be cured but medicine can be given to ease the symptoms.
73
How can pathogens be transmitted?
```
Food and water
Insect bites (animals)
Airborne droplets/ bodily fluids
Direct contact
Indirect contact
```
74
What are the body's natural defences?
Ears - contain wax (which repel insects) and hairs
Lungs - have a lot of mucus to catch any microbes and can then be spat out. There are also small hairs, cilia cells, which move the mucus and stop any microbes.
Eyes - eye lashes, eye lids, eye brows and antiseptic tears.
Nose - hair and mucus
Mouth - antiseptic chemicals in saliva. Tonsils which contain masses of white blood cells.
Stomach - contains hydrochloric acid.
75
What happens if a microbe enters the body?
White blood cells defend your body.
76
What are the 2 ways white blood cells attack microbes?
Macrophage (also known as phagocyte) (non specific response - ingestion of bacteria)
Lymphocyte (specific response - production of antibodies)
77
How does macrophage / phagocyte work?
It's the ingestion of microbes.
A macrophage cell comes close to the microbe. It changes shape to engulf the microbe (pac-man shape) and it then engulfs and surrounds the microbe. It then releases enzymes to destroy the microbe and it spits it out, keeping in anything useful.
78
What's an antigen?
A 'code' like substance on the surface of a microbe which allows your defence system to recognise them.
79
What's an antibody?
They are proteins produced by lymphocytes to counteract / in response to antigens. They work by binding themselves to the antigens, causing them to clump together and will then be destroyed.
80
How do lymphocytes work?
It's a type of white blood cell made from the bone marrow.
T-lymphocytes recognise antigens and either attack directly or coordinate activity of other cells of the immune system.
B-lymphocytes recognise antigens and produce chemicals called antibodies.
Same sized antibodies bind onto the same sized antigens but viruses can change their antigens.
81
What is passive immunity?
When you are given antibodies which you haven't made yourself e.g.
When bitten by a snake, toxins may be released and you must be treated with antivenin which has been produced by injecting and extracting venom from horses.
82
What is active immunity?
When you produce your own antibodies and immunity e.g.
Before going on holiday you are given vaccinations which take a while for your body grow immune to. It isn't instant.
83
What is in an immunity vaccine?
A small amount if dead or weakened pathogen particles.
84
How does bacteria cause disease once in the body?
It reproduces quickly and releases toxins.
85
What medicine kills bacteria within the body?
Antibiotics
86
How does the body protect itself from microbes on the skin if is cut?
Blood clots seal the wounds in skin
| White blood cells kill any microbes which have entered.
87
How may the invasion force of microbes be very large?
Unhygienic conditions
| Contact with infected person
88
What does MMR stand for?
Measles
Mumps
Rubella
89
What is natural active, artificial active, natural passive and artificial passive immunity?
Natural active: when you get a disease and develop immunity to it e.g. Chicken pox
Artificial active: when you get a vaccine for a disease that has been made by dead or weakened pathogens e,g. MMR
Natural passive: when you receive antibodies for a disease from a natural source e.g. Breast feeding
Artificial passive: when you are given antibodies for a disease from an artificial source e,g, snake antivenin
90
How do drug resistant bacteria develop?
Their genes mutate. A random mutation can make them resistant. When we take drugs it kills all bacteria except the resistant bacteria which then has more space and food and can develop.
91
Why do drug resistant bacteria spread so fast?
| 4
It survives on skin
In warm environments
Can't be treated
People with weak immune systems or who are ill or injured can catch it easily.
92
Why are people more likely to get MRSA in a hospital?
Patients are ill and weak so they are vulnerable to catching it as their immune systems would be weaker.
It's very busy and crowded in small spaces, many of the people of which are ill, infected or injured.
Some people have cuts which allows bacteria to enter or even during surgery.
The nurse or examiner could pass it on to another patient who may also have a weaker immune system, being a patient.
Patients with different bacterial infections can lead to the development and mutation of bacteria forming MRSA.
93
What are the 2 main parts to the nervous system?
1. CNS / central nervous system - the brain and spine.
| 2. Peripheral nervous system made up of receptors, sensory nerves, motor nerves and effectors.
94
What's a stimuli?
The changes in the environment which we detect such as chemical, pressure or temperature changes
e.g. Heat from a hot pan
95
What are receptors?
They are what detect the stimuli (changes in the environment) usually sense organs (eyes, ears, nose, skin and tongue) or pain receptors - skin.
96
What are effectors?
An organ or cell that acts in response to the stimuli (change in environment).
Something which carries out / brings about the response, usually by a gland or muscle
e.g. When pricked by a pin, you move away by using muscles in the arm.
97
What is a response?
It's how your body reacts to the stimuli (change in environment) e.g. Moving away or flinching.
98
What are the chain of events from the stimulus to the response?
```
Stimulus
Receptor
Coordinator
Effector
Response
```
99
What's the reflex arc?
A reflex arc is the nerve pathway which makes such a fast, automatic response possible.
100
How does the reflex arc work?
E.g. Reacting to a flame:
Pain receptors in the finger detect the heat from the flame and send a nerve impulse to the spine, in this case through the arm, by the sensory neurone.
The impulse is then passed to the next in the spine by the relay neurone.
Finally, the nerve impulse travels down the motor neurone, in this case down the arm, to the muscle which reacts to the stimulus.
(Order: sensory neurone, relay neurone, motor neurone).
101
What's a reflex?
A fast, automatic, protective response to a stimulus.
102
What are nerves?
Nerves (neurones) are specialised cells that can conduct electrical impulses through the body.
103
What's a synapse?
(As nerve cells aren't joined together) they are the gaps between 2 nerve cells where impulses pass by diffusion of neurotransmitters to continue on the signal.
104
How does a synapse work?
Within a neurone, an electrical impulse travels along an axon (taking information away).
This then triggers the nerve ending of a neurone and releases chemical messengers called neurotransmitters.
The neurotransmitters then diffuse (spread out) across the synapse (gap) and join themselves onto receptor molecules of the next neurone.
The receptor molecules of the second neurone only join onto specific chemicals released from the first neurone.
This then stimulates (increases activity) the second neurone to continue transmitting the electrical impulse.
105
What are the main conditions to be maintained within the body?
Water
Ions
Temperature
Blood sugar
106
What are our main hormones?
Growth - by the pituitary gland • FSH & LH, secreted from birth - 20's, amount affects size
Insulin - pancreas, secreted when glucose levels in the blood rise, diabetics can't produce insulin.
Adrenaline - adrenal, secreted when scared, stressed or excited, prepares body or 'fight or flight'
Thyroxin - thyroid, secreted all the time, too little means you get overweight and vise versa.
Sex -
Male - testosterone, testes, always, controls development
Female - oestrogen and progesterone, ovaries, puberty - 60's, development.
107
What are hormones?
Hormones are chemicals that act like messengers and are secreted by glands and carried in the blood from organ to organ.
108
What is adolescence?
The process where a child is developing to an adult.
109
What are the differences between nerves and hormones?
```
Nerves:
Electrical
Very fast
Lasts a short time
Transported by nerves
Produced by cell body of neurone
```
```
Hormones:
Chemical
Slow
Lasts a lot longer
Transported by blood
Produced by glands
```
110
What's the menstrual cycle?
It is a cycle of ovulation and menstruation controlled by hormones from the ovaries and pituitary gland which cause women to grow an egg, thicken the uterus lining, release the egg and, if the egg is fertilised, maintain the lining otherwise the lining breaks down and the cycle continues.
111
What's FSH?
Standing for follicle stimulating hormone, it is a hormone in men and women which, highest for women in the beginning and end of the menstrual cycle, causes / promotes the growth of an egg or sperm.
112
What's oestrogen?
Found only in women and highest around day 12 of the menstrual cycle, it stops the production of FSH and thickens the uterus lining, promoting the characteristics of the female body.
113
What's LH?
Standing for luteinizing hormone is high around day 13 of MS.
In females, an acute rise of LH triggers ovulation. It causes the egg to be released. In males it stimulates production of testosterone.
114
What's progesterone?
Found in women only and high in day 24 of MS, it maintains the uterus lining and prepares for pregnancy.
115
What are auxins?
Plant hormones
116
Where does growth occur in a plant?
The tip of the shoots and tip of the roots.
117
What's a tropism?
The turning or respond of an organism due to a stimulus, for plants it's with light, gravity and water.
118
What's phototropism?
What plants respond to light by turning to grow towards the light.
This is done because auxins are released on the shaded side of the plant shoot, causing it to grow faster than the side facing the light. (Area of elongation).
This causes the plant to grow more on one side and force the plant to bend towards the light.
119
What is geotropism?
For roots and leaves to serve their purpose, they must be lower / higher.
If the plant is on it's side, auxins gather on the lower half of the stem and root.
Auxins then are produced quickly at the top to stimulate growth in the shoot so it works against gravity and curves upwards.
On the other hand, the roots work with gravity as less auxins are released, causing it to grow slowly and downwards.
