Core Science Flashcards
1
Q
What are characteristics?
A
The features of an organism
2
Q
What is a species?
A
Organisms with many characteristics in common
3
Q
What are the 5 kingdoms?
A
Animalia, Plantae, Fungi, Protoctista, Prokaryotae
4
Q
What are the features of animalia kingdom?
A
Multicellular, heterotrophic, no cell walls, nucleus
5
Q
What are the features of the Plantae kingdom?
A
Multicellular, autotrophic, cell walls (made of cellulose), nucleus
6
Q
What are the features of fungi kingdom?
A
Multicellular, cell walls, saprophytic, nucleus
7
Q
What are the features of protoctista kingdom?
A
Mostly unicellular, nucleus
8
Q
What are the features of Prokaryotae kingdom?
A
Unicellular, no cell walls
9
Q
Define heterotrophic
A
Getting food and digesting the tissues of of other organisms
10
Q
What does autotrophic mean?
A
Make food from small molecules using an energy source, such as light in photosynthesis
11
Q
What does saprophytic mean?
A
Getting food by digesting the tissues of other organisms outside the body and absorbing the digested food
12
Q
Define vertebrate
A
Has a back bone
13
Q
Define invertebrate
A
Has no back bone
14
Q
Describe the features of a fish
A
Gills, poikilotherm, oviparous, external fertilisation
15
Q
Describe the features of an amphibian
A
Gills, poikilotherm, lungs, oviparous, external fertilisation
16
Q
Describe the features of a reptile
A
Lungs, poikilotherm, internal fertilisation, oviparous
17
Q
Describe the features of a bird
A
Lungs, internal fertilisation, homeotherm, viviparous
18
Q
Describe the features of a mammal
A
Lungs, internal fertilisation, homeotherm, viviparous
19
Q
Define viviparous
A
Gives birth to live young
20
Q
Define oviparous
A
They lay eggs
21
Q
Define poikilotherm
A
A species in which its body temperature is dependent on its surrounding environment
22
Q
Define homeotherm
A
A vertebrate which has a regular body temperature
23
Q
Define a species (in terms of reproducing)
A
A group of organisms that can interbreed to form fertile offspring
24
Q
What is a hybrid?
A
Offspring produced from two closely related species that isn’t fertile itself (with the exception of Mallard Ducks)
25
What is a ring species?
A ring of populations, where neighbouring populations can interbreed
26
What is the binomial system?
The naming system for an organism, made up of two Latin words, genus and species
27
What is variation?
Differences in characteristics
28
What is the importance of classification?
To identify species (new and existing)
See how organisms are related
To identify areas of greater and lesser biodiversity
29
Define biodiversity
A measure of the total number of species in an area
30
Why is biodiversity important?
To have foods and medicine
31
Define adaptation
When an organism has characteristics that make it best suited for its habitat
32
What is genetic variation?
Variation in characteristics caused by DNA
33
Give an example of continuous variation
Height
34
What is an acquired characteristic
A characteristic cause by the environment
35
What is classification?
The process of sorting organisms based on their characteristics
36
Why is there competition among a species?
Lack of resources
37
What is natural selection? (Survival of the fittest)
When those with the best adaptations within a species will survive and produce offspring
38
How does evolution occur?
When natural selection happens over an extensive period of time
39
Define speciation
Formation of a new species as when populations of a species are separated geographically and evolve until they are no longer able to reproduce with one another
40
Development of what supports Darwin's theory of evolution?
Resistant organisms
41
What are the 3 main parts of a cell?
Cell membrane, cytoplasm and nucleus
42
Where is DNA found?
In the nucleus
43
What does DNA contain?
Chromosomes
44
Chromosomes are divided up into what?
Genes
45
What is inherited variation?
Variation caused by genes
46
Sort 'eye colour' and 'blue' into allele and gene
Gene - eye colour
| Allele - blue
47
What is a gamete?
Sex cells
48
How many pairs of chromosomes does a gamete have?
23
49
Show the way that a dominant and recessive allele is shown with the letter B
B - dominant
| b - recessive
50
What is the difference between homo and heterozygous?
Homozygous is when a person has 2 of the same alleles and heterozygous is when they have 2 different alleles
51
Define genotype
The alleles for a certain characteristic found in an organism
52
Define phenotype
The characteristic that is caused by the genotype (e.g. Blue eyes)
53
What is sickle cell anaemia?
A genetic disorder that is caused by faulty alleles
54
What are the symptoms of sickle cell anaemia and why does this happen?
People with the disease become tired very easily and often have pain in their joints and their red blood cells are sickle shaped so therefore carry less blood and can sometimes block blood vessels as they stick together
55
What is cystic fibrosis and what does it cause?
A genetic disorder which causes mucus to clog the lungs and enzyme passages which can cause weightloss
56
What is a family pedigree chart used for?
To determine how likely it is for someone to give birth to someone with a certain disease and from there doctors can advise courses of action
57
What is the internal environment?
Conditions inside the body
58
What is the term for keeping the internal environment stable?
Homeostasis
59
What is osmoregulation?
Water control
60
What is blood glucose regulation?
Blood sugar control
61
What is thermo regulation?
Temperature control by the hypothalamus
62
What is the hypothalamus?
The part of the brain the controls temperature
63
Describe was happens to the erector muscles when:
A) you are hot
B) you are too cold
A) the muscle is relaxed so the hair lies flat
| B) the muscle contracts so the hair is upright and acts as an insulator of heat
64
Describe vasoconstriction and vasodilation and when and why they happen?
Vasoconstriction is when the blood vessels tighten to keep the blood flowing through deeper vessels to prevent heat loss through the skin
Vasodilation is when the blood vessels dilate to allow the blood to flow through vessels closer to the surface of the skin to allow the body to lose heat and cool down
65
What do sense organs contain and what do they detect?
They contain reception cells which will detect a stimulus
66
What is an impulse?
And electrical signal created by a receptor cell
67
What do impulses do?
Impulses travel to the brain which can alter things accordingly
68
Impulses travel along neurones, what is this called?
Neurotransmission
69
What do the dendrites do?
They collect impulses from the skin receptor cells
70
What do the impulses travel on before reaching the cell body?
The dendron
71
What do the impulses travel on after passing through the cell body?
The axon
72
What is a nerve?
A bundle of neurones
73
What are the 2 parts of the central nervous system?
The spinal chord and the brain
74
What happens when the brain receives an impulse?
It coordinates a response
75
What happens in a response?
Impulses are sent to effectors to carry out an action
76
What is a sensory neurone?
A neurone that receives impulses
77
What is a motor neurone?
A neurone that carries impulses to effectors
78
What is a relay neurone?
The neurone between the sensory and motor neurone (they make up the spinal chord and the brain)
79
What is the myelin sheath and what does it do?
It is a fatty layer around the neurones to insulate them and carry impulses faster
80
What is a synapse?
A small gap between neurones
81
What are the impulses transmitted across the synapses called?
Neurotransmitters
82
What do synapses do?
They slow down impulses and allow them to only travel in one direction
83
What is a reflex?
An automatic response that bypasses conscious thought (the brain)
84
What is the reflex arc?
When a sensory neurone directly controls a motor neurone (bypasses the brain which is made up of relay neurones)
85
What are hormones produced by?
Endocrine glands
86
What is the name of an organ that responds to hormones?
Target organ
87
What does the pituitary gland do?
It causes the kidney to release concentrated urine
88
Where is adrenaline released from and what does it do?
It is released from the adrenal glands and speeds up our heartbeat
89
Where is oestrogen made and what does it do?
Made in the ovaries and causes female reproductive development
90
Where is testosterone made and what does it do?
Made in the testes and causes male reproductive development
91
What does the pancreas do when blood sugar is too high?
It secretes insulin which will convert glucose into glycogen (a store of glucose) to lower blood levels, this happens in the liver
92
What is the role of glucagon and where is it made?
It breaks down glycogen into glucose when blood sugars are low, it is made in the pancreas
93
What is diabetes?
It is a disease caused by the inability to control blood glucose levels as the body either has no insulin or doesn't respond to it
94
What is type 1 diabetes?
Type 1 is when the pancreas doesn't produce insulin, people with type 1 need to inject insulin daily into the subcutaneous fat layer
95
What is type 2 diabetes and what causes it?
Type 2 diabetes occurs when the persons body no longer responds to insulin, it is caused by high fat diet, lack of exercise, getting older and being obese
96
What do doctors class as obese?
Someone with a BMI over 30
97
How do doctors work out BMI?
Weight (kg) / height squared (m^2)
98
Define tropism
Growing towards or away from something
99
What is a phototropism?
A tropism caused by light
100
What is the name of the plant hormone that causes phototropism?
Auxins
101
How do auxins cause phototropism?
They move to the shaded side of the plant and cause cell elongation
102
What type of tropism do plant roots have?
Gravitropism
103
What do the auxins in roots do?
They follow the direction of gravity and prevent cell elongation in this area so the root grows in the direction of gravity
104
What do gibberellins do and when?
After a period of germination and the plant has had time to grow, the gibberellins will be released to turn starch into sugar and stimulate flower or fruit production
105
Name four uses for plant hormones
Selective weed killer
Rooting powder
Seedless fruit
Fruit ripening
106
Describe how selective weed killers work
Artificial auxins are used to make broad leaf plants grow out of control and die but leave narrow leaves plants unaffected
107
How do rooting powders work?
Plant cuttings are dipped into the rooting powder (which has synthetic auxins in) which makes them develop roots quickly
108
Explain how we get seedless fruit
Flowers are strayed with plant hormones so that the fruit develops without seeds, they can also make small seedless fruit bigger (e.g. Grapes)
109
How are plant hormones used to ripen fruit?
They (gibberellins and ethylene) are sprayed onto fruit trees to prevent the fruit from falling also they are sprayed to make them ripen so the fruit gets to the shops in perfectly ripe condition
110
What is a drug?
A chemical substance that changes how the body works
111
What do narcotics do?
They make us sleepy
112
What's a hallucinogen?
A drug which changed how our brain responds to what we see, hear or feel (e.g. LSD distorts our sense of colour, time and space)
113
What does a stimulant do?
Speeds up Neurotransmission thus speeding up reaction time
114
What does a painkiller do?
They block nerve impulses so we feel less pain
115
What is a depressant?
A drug that slows down neurones in the brain to help relaxation
116
What does tar contain and what is the harm?
Tar contains carcinogens which can cause cancers in the mouth and lungs
117
What are the dangers of carbon monoxide?
It reduces oxygen
Makes blood vessels narrower which can kill tissues which are then more vulnerable to infection
Can cause heart attacks and cause respiratory diseases
118
What is the problem with nicotine?
It is the addictive drug in tobacco, people can become addicted after just 4 cigarettes
119
Describe the short term effects of alcohol?
Slows down brain and CNS, slows reaction times, lowers inhibitions, blurred vision, poor coordination and can cause unconsciousness
120
What are the long term effects of alcohol?
Cirrhosis of the liver (the normal tissue is destroyed so it cannot function properly), brain damage, clotting in the brain and alcoholism
121
What happens in a transplant?
A healthy organ is taken from a donor and put into a patient to replace non-functioning organs
122
What are the 4 main points doctors have to follow when finding a donor?
Similar tissue types
Similar age
Geographically close
How ill the patient is
123
What is an ethical decision?
A decision made that uses a criteria to reach a solution that most people think are fair
124
What is a pathogen?
A harmful microbe which carries infectious diseases
125
What 4 things are diseases caused by?
Bacteria, viruses, fungi and protoctists
126
Name the 6 ways that disease are spread
```
Water
Vectors: mosquitoes/houseflies
Food
Contact
Airborne
Body fluids
```
127
What two methods do animals have to fight pathogens?
Physical barriers and chemical defences
128
Define antiseptic
A substance that kills microbes from out side the body
129
What do plants use to prevent pathogens from causing harm?
Anitbacterials
130
Give two examples of how humans use antibacterials
Witch hazel - used in aftershaves to prevent infection
| Mint - used in toothpaste
131
Give some examples of physical barriers in humans
Skin, sweat, cilia (tiny hairs that sweep away mucus and microbe from the lungs), mucus to trap microbes
132
Give some examples of chemical defenses
Hydrochloric acid in the stomach and lysozyme in tears
133
Name one example of a resistant bacteria and why it is resistant
MRSA - because antibiotics have been over used
134
What is a producer?
Something that makes its own food (e.g plants)
135
What is a primary consumer?
Something that eats producers
136
What is a secondary consumer?
Something that eats a primary consumer
137
What is a trophic level?
A level on the food web (e.g. Primary consumers)
138
Why are food webs useful?
They show feeding relationships and that animals are interdependent
139
What is a pyramid of biomass?
It shows the biomass (that quantity of organism and the energy that it can transfer) of organisms in an area at each trophic level
140
What is parasitism?
When two organisms live together, the parasite feeds on the host and harms it
141
What do fleas and headline do that classifies them as a parasite?
They bite on animals to feed on their blood
142
What do tape worms do?
They live in intestines and eat the hosts food causing weightloss, they can sometimes even block intestines
143
What are the adaptations of a tape worm that makes it suitable for living in the intestine?
Flat body which results in a large surface area for maximum food absorption, it has substances on its skin to prevent it being digested, hooks and suckers instead of eyes, and there are male and female reproductive parts on each segment
144
What does mistletoe do?
The roots grow into the host's vessels (tree) to absorb water and mineral salts
145
Describe a mutual instil relationship
When two organisms live together and both benefit from the relationship
146
What do oxpeckers do?
They feed on parasitic insects off the herbivore
147
What do cleaner fishes do? (Mutualism)
They feed on parasitic organisms on the surface of shark skin
148
What does nitrogen fixing bacteria do in terms of mutualism?
Feeds on chemicals for food and produces the nitrogen compounds that the legumes need to grow
149
What does chemosynthetic bacteria do?
It gets the substances needed from the tube worms and the tube worm will feed on the waste from the bacteria
150
What are fertilisers made up of?
Phosphates and nitrates
151
Describe eutrophicationi
1) fertiliser added 2) rain washes fertiliser off 3) phosphates and nitrates dissolve in soil water 4) phosphates and nitrates wash into flowing water 5) high levels of phosphates and nitrates encourage plant and algae growth 6) surface plants block the light so plants die 7) deco losers increase and use oxygen 8) oxygen decreases 9) animals die from lack of oxygen
152
What is an indicator species?
A species that can show where pollution occurs
153
How does black spot fungus in roses show areas of pollution?
Black spot fungus is killed by sulfur dioxide
154
How do lichens act as an indicator species?
Different species can to,erase different levels of sulfur dioxide so we can tell absence of these gases in air
155
How do stonefly larvae and freshwater shrimp show pollution on water?
They need lots of oxygen so would show an area with little pollution
156
How do bloodworms and sludge worms show us polluted areas of water?
Because they can survive in areas with little oxygen
157
Death and excretion leads to what stage in the nitrogen cycle?
Protein and urea
158
What happens to protein and urea to convert it to ammonia?
It is decomposed by soil bacteria
159
Ammonia is _____ by ____ to turn it into nitrates in the soil
A) oxidised
| B) nitrifying bacteria
160
How are nitrates broken down into nitrogen in the air?
By denitrifying bacteria
161
Nitrogen fixing bacteria and lightning do what to nitrogen in the air?
Turn it into nitrates in the soil
162
Nitrates are _____ by roots
Absorbed
163
How does nitrogen in air lead to plants in the nitrogen cycle?
Nitrogen fixing by root nodule bacteria
