🍃Biology Paper 2 Flashcards
1
Q
Bio: what is selective breeding
A
2 animals with desired characteristics are selected and breaded. Repeat over generations.
2
Q
bio: name reasons that organisms need energy
A
- homeostasis
- muscle contraction
- growth
3
Q
Bio: what tissue differentiates in plants
A
Meristem cells
4
Q
Bio: what is a gene
A
It is a short segment of DnA that encodes for one protein
5
Q
Bio: what do 3 base pairs encode for
A
One amino acid
6
Q
Bio: what is a phenotype
A
The observable characteristics of an organism due to its genotype
7
Q
Bio: what is a genotype
A
The combination of alleles that a person has for a particular trait (AA, Gg, cc)
8
Q
Bio: what is polydactyl
Is it dominant or recessive?
A
More fingers or toes, dominant (PP, Pp)
9
Q
Bio: what is cystic fibrosis, dominant or recessive?
A
It’s inherited disorder of cell membranes that mainly affects the lungs and digestive system they can become clogged with lots of thick, sticky mucus as too much is produced, recessive (ff)
10
Q
Bio what are the sex chromosomes for a male
A
XY
11
Q
Bio: what are the chromosomes for a female
A
XX
12
Q
Bio: what is meristem
A
Meristems are regions of unspecialised cells in plants that are capable of cell division
13
Q
Bio: what are the villi
A
finger-like projections that increase the surface area over which molecules are defused into the blood through the small intestine or the uterus
14
Q
Bio: what types of screening are used during a pregnancy
A
- family history
- pre-screening-12m week nuchal fold thickness, this can indicate the presence of Down’s syndrome
- afp blood test
15
Q
bio: what is a chlorophyll deffeciency
A
chlorosis
16
Q
bio: what stage of mitosis is happening here
A
prophase
17
Q
bio: what stage of mitosis is happening here
A
Metaphase
18
Q
bio: what stage of mitosis is happening here
A
Anaphase
19
Q
bio: what stage of mitosis is happening here
A
Telophase
20
Q
bio: what stage of mitosis is happening here
A
cytokinesis
21
Q
Bio: what are the properties of meiosis
A
- 4 cells are produced
- non-identical cells are produced
- DNA is replicated once
- cells have 23 chromosomes so gametes are produced
22
Q
Bio: what are the properties of mitosis
A
- creates 2 identical cells
- DNA is replicated once
- there are the full 46 chromosomes in each cell
23
Q
Bio: what is a diploid cell
A
A cell with the full amount of chromosomes is humans 23 pairs so 46 chromasones
24
Q
Bio: what are gametes
A
They are sex cells, sperm and egg
25
Bio: what is the name for the enzyme that removes a gene used in genetic engineering
Restrictive enzyme
26
Bio: what enzyme is used to join 2 ends of DNA in genetic engineering
Ligaze
27
Bio: what is a trophic level
It is a level of consumers
28
Bio: where does the energy in a food chain come from
The sun
29
Bio: what is a hormone
- It is chemical released by a gland that is carried through the blood to a target organ and effect a responce
- A chemical messenger
30
Bio: where are hormones produced
Endocrine glands
31
Bio: where is insulin produced
Pancreas
32
Bio: biogas generators
They are an industrial device that completes anaerobic decomposition to produce methane that is in biogas
33
Bio: what organisms are decomposers
- insects
- fungi
- bacteria
- larvae
34
Bio: what does decomposition do
It returns nutrients to the environment and turns large organic compounds into simple molecules
35
Bio: how to bacteria and fungi digest
They excrete digestive enzymes onto the organic matter and then absorb the nutrients.
36
Bio: how do fungi and bacteria digest organic matter
They excrete enzymes onto the matter and then absorb the nutrients (Saprophytic)
37
Bio: what is a Saprophytic organisim
It is an organism that excretes enzymes onto its food and then absorbs the nutrients.
38
Bio: what are the 3 factors that effect the rate of decomposition
- temperature
- water concentration
- oxygen concentration
39
Bio: what is anaerobic decay and **what** does it produce
This occurs when there is not enough oxygen present during decay and produces biogas which is mostly composed of methane, a good fuel
40
Chem: what is biogas mostly composed of
Methane, a good fuel
41
Bio: what is the carbon cycle
- producers remove CO2 from the atmosphere by photosyntheses
- animals eat theses plants and absorb carbon compounds
- animals perform respiration which releases carbon dioxide into the atmosphere
- animals die and decomposers release carbon compounds into the atmosphere
- also carbon can be released by the combustion of fossil fuels.
42
Bio: why does too much water hinder the rate of decay
Oxygen cannot get to the Side of decomoposition
43
Bio: rate of change equation for rate RP
Rate of change = change in indicator / time
44
Bio: what is the amount of biomass transferred between trophic levels
5-10%
45
Bio: what is homeostasis
It is the regulation of internal conditions at optimum levels in response to external changes
46
Bio: what is it called when the blood vessels widen
Vasodialation
47
Bio: what is it called when the blood vessels tighten
vasoconstriction
48
Bio: what is a control system
Automatic responses they use nervous and chemical responses, they consist of receptors, control centeres and effectors
49
Bio: what does a receptor do
It detects changes in internal or external environments
50
Bio: what do control centres do
They are areas that receive and process info from receptors and coordinate body response
51
Bio: what do effectors do
They affect a responce
52
Bio: through what are signals sent to and from the brain
Neurones
53
Bio: what are the 2 main parts of the nervous system
- **brain** - coordinates the response of the effectors
- **spinal cord** - the control centre for reflex response, important to coordinating the response of the effectors to environmental changes, reflex responce
54
Bio: what is a reflex
An involuntary action the is automatic, a rapid response to a stimulus
55
Bio: what does ADH stand for
Anti Diuretic hormone
56
Bio: what does the pupil reflex do
It is the dilation of the pupil
57
Bio: what are the receptors that detect changes in temperature
thermoreceptors
58
Bio: what is the knee jerk reaction
sudden kicking movement of the lower leg in response to a sharp tap on the patellar tendon, which lies just below the kneecap
59
Bio: what are 2 respiratory reflexes
Coughing
Sneezing
60
Bio: what control centre do reflexes not include
The brain
61
Bio: where do synapses occur
At each junction of a reflex ark
62
Bio: what are synapses
They are gaps between the neurones
63
Bio: what is a reflex ark
Stimulus
- receptor
- sensory neurone
- relay neurone (**coordiantor**)
- motor neurone
- effector
Responce
64
Bio: what are the chemicals that carry signals across the gap between the neurones
Neurotransmitters
65
Bio: how do the synapses work
Neurotransmitters move down the concentration gradient toward the other receptor and bind to it, this then repeats the signal
66
Bio: what is tropisim
Response of a plant to a stumulus
67
Bio: what is geotropism
It is the response of a plant to gravity/orientation
68
Bio: what is positive gertropisim
It is the movement of a part of a plant toward the centre of gravity (**roots**)
69
Bio: what is negative gertropisim
It is the movement of a part of a plant away from the centre of gravity (**shoots**)
70
Bio: what does auxin do in roots
It inhibits growth, drives them down
71
Bio: what does auxin do in shoots
It promotes growth
72
bio: what type of cells only have one copy of each chromosome
haploid cells
73
bio: what is known as a permanent change to the sequence of nucleotides
a mutation
74
Bio: in what does auxin cause positive geotropisim
Roots
75
Bio: what is phototropisim
It is the response to the stimulus of light
76
Bio: what is geotropisim
It is the response to the stimulus of gravity
77
Bio: in what does auxin cause negative geotropisim
Shoots
78
Bio: how does auxin cause plants to grow towards light
Light breaks down auxin, auxin encourages growth and so the plant grows toward the light
79
Bio: what is myopia
It is short sightedness
80
Bio: what is hyperopia
It is long sightedness
81
Bio: what is astigmatisim
It is an asymmetry in the cornea/lens
82
Bio: what is the cornea
Refracts light - bends it as it enters the eye
83
Bio: what is the iris
It controls how much light enters the pupil
84
Bio: what does the lens do
Further refracts light
85
Bio: what is the retina
Contains the light receptors
86
Bio: what is the optic nerve
Carries impulses between the eye and the brain
87
Bio: what is the sclera
Tough white outer layer of the eye, helps protect eye from injury
88
Bio: what are the 2 homeostatic prosesses in the eye
- accommodation - focusing ciliary muscle relaxes
- light intensity - greater the intensity smaller the apature
89
Bio: what is accomodation in the eye
Accommodation - homeostasis of the eye - focusing - far away, ciliary muscle relaxes and suspensory ligaments tighten, lens becomes thin
90
Bio: what is light intensity homeostasis in the eye
Light intensity, greater the intensity smaller the apature
91
Bio: what does the cerebrum do
Higher thinking
92
Bio: what does the cerebellum
Balance and control
93
Bio: what does the hypothalamus do
It controls:
- body temp
- hunger
- mood
- sex drive
- blood pressure
- sleep
- thirst
94
Bio: what does the medulla oblongada do
It controls:
- heartbeat
- breathing
- blood pressure
95
Bio: what does the pituatary gland do
It regulates growth and metabolism and produces hormones that control other gands
96
Bio: what affect does light have on the roots
Auxin builds up facing down, light source is up, auxin breaks down in present of light, auxins in roots inhibit growth and so the part facing the light grows more moving the plant away from the light
97
Bio: what are the 3 main uses of auxin
- **plant clones** - tissue culture
- **rooting** - taking cuttings of a plant and use rooting compound (contains auxin) to stimulate root growth in cutting)
- **weedkiller** - too much auxin can ruing a plants growth cycles killing it
98
Bio: what does ethene do in plants
Controls cell division during growth
99
Bio: what can ethene be used for in plants
It can be used to ripen plants for sale after transport
100
Bio: what does gibberelin do
Controls growth and development
101
Bio: what are the uses of gibberelin
- **controlling dormancy** - inducing germination
- **inducing flowering**
- **growing larger fruits**
102
Bio: what part of the plant produces auxins
The tip
103
Bio: what does dna encode for
Protiens
104
Bio: what is a nucleotide of dna
It is one sugar one phosphate and a bace
105
Bio: what is the sugar phosphate backbone
106
Bio: what is mRNA
It is messenger RNA
107
Bio: what is tRNA
It is transfer RNA
108
Bio: what is tRNA specific to
It is specific to one codon
109
Bio: what is a codon
It is a specific combination of 3 baces
110
Bio: what is it that goes along the DNA and copies it
It is RNA polymerase
111
Bio: explain the process of protein synthesis
- RNA Polymerase (an enzyme) goes along the DNA and copies it creating mRNA
- the mRNA leaves the nucleus and is bonded to by a ribosome
- mRNA is fed through the ribosomes and each codon of 3 baces pairs is read by an anticodon (with tRNA at the end)
- by this the next amino acid "added" to the growing chain which then becomes a protein
112
Bio: what is variation in terns of inheritance and responce
It is the difference between individuals
113
Bio: what are the 2 types of twins in humans
- dizygotic - like 2 separate pregnancies
- monozygotic - identical
114
Bio: what type of pregnancy makes identical (monozygotic) twins more common
Artificial insemination
115
Bio: what are the male plant gametes
They are pollen
116
Bio: what are the female plant gametes
Egg cells
117
Bio: what are the stages for genetic engineering
| enzymes
1. Enzymes isolate the required gene and then it is inserted into a vector (such as bacterial plasmid or virus)
2. Vector transports gene to required cell
3. Genes are transferred at the early stages of development to ensure that the organism develops with the wanted characteristics
118
Bio: what are 4 abiotic factors that could affect the population of a species
- water
- oxygen / air
- temperature
- minerals
- pH
119
Bio: what are 4 biotic factors that could affect the population of a species
- food
- predators
- disease
- one species outcompeting another so the numbers are no longer sufficient to breed
120
Bio: how many times is the DnA replicated in meiosis
1
121
Bio: how many times is the DnA replicated in mitosis
1
122
Bio: how do identical twins occurs
1 egg is fertilised and early on in its division it splits into 2 eggs
123
Bio: how do non-identical (fraternal) twins occur
2 eggs 2 sperm
124
Bio: how was the first sheep cloned
1. They egg 1 taken from ewe one, nucleus is taken out
2. A nucleus from ewe 2 is taken from the cells and added to the egg, it begins to divide
3. The embryo is put in the uterus of ewe 3
125
Bio: what type of organisms do binary fission and what what type of cells are produced
Procaryotes, clones
126
Bio: in cloning is the egg cell fertilised or not
Not
127
Bio: what are plant stem cells
| property
They are pluripotent, they can divide to become any type of cell
128
Bio: what is deamination
It is the breakdown of proteins and the creation of amino acids, its process is this:
1. protein
2. amino acid
3. ammonia
4. urea
129
Bio: where is the site of deamination
It is in the liver
130
Bio: how did Charles Darwin prove tropisim
- he took some plants, removed the tips, and covered them with an opaque cap, a cylinder
- he found that the tip grew straight up, when the tip was covered by a transparent cap, it moved towards the light
- he also covered the site of curvature and found that it went towards the light
131
Bio: what type of lens can be used to correct myopia
A concave lens
132
Bio: what type of lens can be used to correct hyperopia
A convex lens
133
Bio: what is the homeostatic reaction to the cold
- shivering - movement, muscles release more though respiration energy and so heat
- **vasoconstriction** - reduced blood flow to the extremities such as the arms
- goosebumps - raises hairs and traps air near the skin
134
Bio: what is the negative feedback loop of blood glucose control
135
bio: what is the endocrine system
it is the hormonal system, it uses chemical messengers (hormones) instead of nerves
136
bio: what does thyroxin control
basal (resting) metabolic rate
137
bio: how does thyroxin operate
- when the concentration of thyroid hormones (such as thyroxin) is low TSH (thyroid stimulating hormone) is released that stimulates the production of thyroxin
- when the conc of thyroid hormones is high, TSH production decreases
138
bio: what releases thyroxin
the thyroid gland
139
bio: what does thyroxin do in young animals
it regulates growth and brain development
140
bio: where is adrenaline released
the adrenal gland
141
bio: **what** does adrenaline control and **what** does it stimulate these things to do
- **heart rate** - it increases this
- **lungs** - it enlarges the air passages in the lungs and alters the metabolism to boost delivery of oxygen and glucose to the brain and muscles
- **fight or flight** - adrenaline prepares the body to more and think quickly
142
bio: what effect does adrenaline have on the lungs
143
Bio: where is the relay neurone located
In the **spinal cord**
144
Bio: why is the relay neurone important
It cuts out the brain, increasing speed
145
Bio: what does adrenaline do to the pupils
It dilates them
146
Bio: what does adrenaline do to the heart rate and blood pressure
It increases blood pressure
147
Bio: what is the effect of too much glucose on the body
It can have a negative affect to osmosis by affecting concentration gradients
148
Bio: what is the effect of too little glucose
Less glucose for respiration
149
Bio: in what organ is the glucose detected
The pancreas
150
Bio: what is the treatment for kidney failure
Dialyses
151
Bio: what is the process for dialysis
- patients blood flows through the machine
- the machine contains dialysis fluid that has the optimum levels of water, glucose, ions for a healthy persons blood
- patients blood passes over a semi permeable membraine in the dialysis fluid that replicated the kidney tubes
- the dialysis fluid created as a concentration gradient and excess ions and glucose diffuse from one side to another
- the filtered blood then returns back to the body
152
Bio: what are the pros of dialysis
- life saving
- more time to find a donor kidney
153
Bio: what are the cons of dialysis
- needed 3 times a week and takes 3 - 4 hours
- expensive
- increased risk of clots and infections
154
Bio: who can give a kidney transplant
- a close relative
- someone who has recently died, on the organ donor register, with a tissue match
155
Bio: what do most people who have had a kidney transplant have to take for the rest of their life’s and why
- immunosuppressants
- to stop their immune system from attacking the foreign kidney cells
156
Bio: what factors can affect the water balance
- sweating
- eating too much salt
- exhalation - water lost from lungs by the breath
- illness
157
Bio: how is urine produced (2 processes)
Each kidney contains very small structures called nephrons, these stages happen at them:
- urafiltration
- selective reabsorbtion
158
Bio: what is the process for urafiltration
The blood is filtered, all water, urea and salts move into the nephron tubules, blood cells and proteins remain in the blood as the are too big to move across the capillary walls
159
Bio: what is the process for selective re-absorption
Useful substances including water in the nephron are re-absorbed from the nephron tubule back into the bloodstream, this leaves urea, excess water and salts in the tubule, this mixture forms urine that then moves to the bladder
160
Bio: what hormone controls the water concentration in the blood
**ADH** - anti-diuretic hormone
161
Bio: what is the process for the control of water concentration in the blood
- too little water, when there is too much water in the blood, the **hypothalimus** triggers the **pituitary gland** to release AHD, this increases the permeability of the of the kidney tubes meaning that more water is re-absorbed, this means that there is a small volume of water in the urine
- too much water, hypothalimus triggers the pituitary gland to stop releasing ADH and the water re-absorbed decreases as the permeability of the kidney tubes decreases
162
Bio: define permiability
The ability of things to pass through
163
bio: what are the suspensory ligaments
They are a ring of fibres that connect the ciliary muscles to the lens
164
Bio: what are the ciliary muscles
They are a ring of smooth muscle that can change the shape of the lens, this is the way the eye focuses light
165
Bio: how does the eye focus on a close object
The ciliary muscles contract, the suspensory ligaments loosen, the lens becomes thicker and rounder, light is refracted significantly
166
Bio: how does the eye focus on things far away
They ciliary muscles relax and the suspensory ligaments tighten, the lens becomes flatter and thinner, light is refracted less
167
Bio: what is retina scanning
Retina scanning looks at the pattern of blood vessels in your retina to identify you
168
Bio: what is the male response to puberty
- testosterone rises, sperm produced
- underarm, facial and pubic hair grow
- voice deepens
169
Bio: what is the female response to puberty
- oestrogen rises, mensural cycle is triggered
- underarm and pubic hair grows
- breasts enlarge
170
Bio: what are the 4 hormones that control the mensural cycle
- FSH
- oestrogen
- LH
- progesterone
171
Bio: what does progesterone do
It is responsible for maintaining the uterine lining
172
Bio: what are the 3 ways of **fossils** being produced
- soft materials harden, this can produce casts or impressions
- preservation, where decomposers cannot act, e.g. extremely low temps, preservation is possible
- mineral replacement, hard parts of organisms are gradually replaced by minerals as they slowly decay, this creates a rock like substance
173
Bio: what things can cause slower extinctions
geological and atmospheric changes, over a longer period
174
Bio: what can cause short term extinctions
- large volcanic eruptions
- meteorite impact
175
Bio: how is a community stable
When all the species and environmental factors are balanced and population sized stay more or less constant
176
Bio: what are quadrant and what are they used for
they are square frames that can be used to estimate population sizes
177
bio: what is a transect and what/how is it used
- they can be used to investigate the effect of a factor on that distribution of a species
- a transect line is a piece of tape that is stretched across that habitat of interest
- quadrantal re placed at regular intervals along the line
178
Bio: what is peat and how does it effect climate change
It is a deposit of partially decayed matter, destruction of peat bogs had become more common, they are destroyed by burning or decay, these processes release carbon dioxide into the atmosphere, this also **decreases biodiversity**
179
bio: what can gardeners use peat for
compost
180
Bio: what are the 3 forms of hormonal contraception that do not have to be taken daily
- contraceptive patch - releases progesterone, lasts a week
- implant - lasts for 3 years, releases small amounts of progesterone
- injection - up to 3 months, contains progesterone
181
Bio: what are the 2 types of contraceptive pill
- combined pill
- progesterone only pill
182
Bio: how does the progesterone only pill work
- stimulates production of thick slimy mucus, very difficult for sperm to penetrate
- inhibits the release of FSH (and LH) so eggs don't mature
183
Bio: how does the combined pill work
- contains both oestrogen and progesterone
- taken every day, enough oestrogen builds up to inhibit the production of FSH (and LH) so no eggs mature
184
Bio: what are the 2 types of contraception that are inserted into the woman's body
- diaphragms - a shallow plastic cup, inserted into vagina before intercourse and sits at the entrance to the uterus, prevents sperm from reaching the egg, can be covered in spermicide that can kill sperm
- IUDs (intrauterine devices) - aka the coil, t shaped devices inserted into the uterus, they prevent the implant of an embryo, some of the also release progesterone
185
Bio: what are the 3 types of male contraception
- condoms
- sterilisation
- natural methods - timing so as not to have intercourse during ovulation
186
Bio: how can men be sterilised
Sperm ducts are cut, so sperm not released on ejaculation
187
Bio: how can women be sterilised
Fallopian tubes cut, eggs cannot reach the uterous
188
bio: what are 3 roles of proteins in the body
- enzymes
- haemoglobin
- antibiodies
189
Bio: what is food security
It will be achieved when the whole global human population has access to enough food to stay healthy
190
Bio: what are the factors that can affect the goal of achieving food security
- birth rates
- new plants/pathogens
- extreme meteorological events
- conflicts
- costs of agricultural inputs
- diet shifts
191
Bio: what is mycoprotein, properties, who’s it for?
It is a food source that is high in fibre and low in fat, suitable for vegitarians
192
Bio: how is mycoprotein produced
It is produced by growing the fungus *fusarium* in VATS called fermenters under aerobic conditions, by using glucose syrup as a food source
193
bio: what are the 2 types of biotechnology you need to know
- growing microorganisms for food (mycoprotein)
- genetic modification
194
Bio: what is an example of a genetically modified crop
**golden rice** - it is a genetically modified rice that contains a molecule that helps make vitamin A
195
Bio: what is golden rice modified to contain
A molecule that helps make vitamin A
196
Bio: what affects can declining fish stock have
- financial issues
- food security is threatened
- food chains are affected
- populations can be at risk
197
Bio: what are sustainable fisheries
Sustainable fisheries do not catch fish at a faster rate than they can reproduce
198
Bio: what allow sustainable fisheries to operate
- net sized is regulated
- fishing quotas
199
Bio: what are fishing quotas
They restrict the number and size of fish that can be legally caught
200
Bio: how is net size regulated
Controlling the size of the holes in the nets allow the smaller and younger fish to slip though the net so they can survive (at least) to maturity
201
Bio: why do farmers feed their animals high protein foods
Because it can boost their growth rates
202
Bio: why does shortening food chains increase farm efficiency
Only abt 10% of energy passes between the trophic levels, stopping this greatly increases efficiency
203
Bio: how can energy be saved when rearing livestock (by limiting their energy expendature
Keeping them warm and limiting their movement
204
Bio: what is the fungus that is used to make mycoprotien
*fusarium*
205
Bio: why do fruit ripen faster when in the presence of banana
Becausee they release ethene which causes them to ripen faster
206
Bio: how do non-coding (those that don't code for proteins) affect the expression of genes
They can turn genes on/off
207
Bio: where in the brain in the hypothalimus
208
Bio: where in the brain is the cerebellum
209
bio: where in the brain is the Medela oblongada
210
Bio: where in the brain is the cerebrum
211
Bio: what is a mutation
a change in the DNA sequence of an organism
212
Bio: what hormones are used for fertility treatment
FSH
LH
Multiple eggs can be released
213
Bio: what day does ovulation occur
~day 14
214
Bio: what is a pyramid of numbers
shows the total number of individual organisms at each level in the food chain (trophic level) of an ecosystem
215
Bio: What is a pyramid of biomass
represents the mass of organisms at each trophic level
216
Bio: how do modern biological techniques help our ability to culture microorganisms
They allow us to be able to grow microorganisms in large quantities for food
217
Bio: how do we produce insulin to treat people with diabetes
a genetically modified bacterium produces human insulin, when it is harvested and purified I can be used to treat people with diabetes
218
Bio: what is happening to the fish stocks in the oceans
They are declining
219
Bio: what are some biological factors that affect food security
- increased birth rate - more people
- changing diets means scarce food resources are transported around the world
- new pests and pathogens
- environmental changes
- cost of agricultural inputs
- conflicts which can affect availability of food
220
Bio: what are producers (2 examples)
They are mostly plants and algae
221
Bio: how much of the incident energy of light from the sun do producers convert into energy
~1%
222
Bio: what are losses of biomass due to
- not all material is ingested, some is egested as faeces
- some absorbed material is lost as waste, such as carbon dioxide and water in respiration and water in urea and urine
- large amounts of glucose are used in respiration check if last oun counts with sir
223
Bio: on a pyramid of biomass where is trophic level 1
It is at the bottom of the pyramid
224
Bio: what is at level one through 4 in trophic levels
- level 1 - plants and algae, producers
- level 2 - herbivores eat plants, primary consumers
- level 3 - carnivores eat herbivores, secondary consumers
- level 4 - carnivores eat other carnivores tertiary consumers
225
Bio: what are apex predators
They are carnivores with no predators
226
Bio: what do decomposers do
They break down dead plant and animal matter by secreting enzymes into the environment, small soluble food molecules then diffuse into the organisim
227
Bio: what are some ways that scientists and concerned citizens have tried to maintain biodiversity
- breeding programs
- protection and regeneration of rare habitats
- re-introduction of field margins and hedge rows
- reduction of deforestation
- recycling of resources rather than putting waste in landfill
228
Bio: what has large deforestation in tropical areas be done for
- to provide land for cattle and rice fields
- to grow crops for biofuels
229
Bio: what are 2 ways peat releases carbon dioxide into the environment
- decay
- buring of the peat
230
Bio: what might cause environmental changes
- the seasons
- geographical changes
- human interaction based changes
231
Bio: what is biodiversity
It is the variety of all of the different species of organisms on earth or within and ecosystem
232
Bio: what does great biodiversity ensure
It ensures the stability of ecosystems by reducing the dependency of one species on another for food, shelter and the maintenance of the physical environment
233
Bio: what are human activities doing to biodiversity
They are reducing it, only recently have measures been introduced to try to stop this reduction in biodiversity
234
Bio: what relevance does biodiversity have to the human species survival
The future of the human species on earth relies on maintaining a good level of biodiversity
235
Bio: what affects does an increased human population have on the amount of waste produced
More humans (**and an increased standard of living**) mean that more resources are used and more waste is produced
236
Bio: what will happen if waste and chemical materials are not handled properly
More pollution will be caused
237
Bio: what 3 places can pollution occur
- air
- land
- water
238
Bio: what are the types of pollution that can occur on land
- landfill
- toxic chemcals
239
Bio: what are the types of pollution that occur in water (like where are they from)
- from sewage
- fertilisers
- toxic chemicals
240
Bio: what are the types of pollution that can occur in air
- smoke
- toxic gas
241
Bio: what does the destruction of peat bogs do
It **decreases biodiversity**
242
Bio: what happens to the number of predators and prey on stable communities
They rise and fall in cycles
243
Bio: what produces all of the biomass on earth
Photosynthetic organisims
244
Bio: what do all food chains begin with
Producers
245
Bio: what is an example of an extromophile
Bacteria living in deep sea vents
246
Bio: what are the 3 types of adaptations of organisims
- structural
- behavioural
- functional
247
Bio: what do organisms need to survive and to reproduce
A supply of materials from their environment and from other living organisims
248
Bio: in a community or habitat what do plants often compete with eachother for
- light
- space
- water
- mineral ions
249
Bio: in a community or ecosystem what do animals often compete with each other for
- mates
- food
- territiory
250
Bio: what is is called when, if one species is removed, it affects the whole ecosystem
interdependence
251
Bio: what is a stable community
It is one where all the species and environmental factors are in balance so population sizes remain constant
252
Bio: what do gardeners do to make compost
Gardeners and farmers try to provide optimism conditions for rapid decay of waste and biological material
253
Bio: what do farmers and gardeners use compost for
It is used as a natural fertiliser for growing garden plants and crops
254
Bio: what is an ecosystem
It is the interaction of a community of living organisms (biotics) with the non-living (abiotic) parts of their environment
255
Bio: what does homeostasis do
It maintains optimal conditions for enzyme action and cell function
256
Bio: what type of responses do homeostatic reactions occur
Nerovus and chemical responces
257
Bio: what do all control systems include
- receptors - cells which detect stimuli
- effectors - muscles or glands
- **coordination centers**
258
Bio: what are receptors
They are cells which detect stimuli
259
Bio: what are effectors
They are muscles or glands which bring about responces which restore optimum levels
260
Bio: what part of the brain do reflex actions not incude
The conscious part
261
Bio: what is the brain made of
it is made of billions of interconnected neurons and had different regions that carry out functions
262
Bio: how were regions of the brain mapped
Neuroscientists have been able to map regions of the brain by studying patients with brain damage, electrically stimulating different parts of the brain and using MRI scanning techniques, the complexity and delicacy of the brain makes investigating and treating disorders very difficult.
263
Bio: what is the eye
It is a sense organ containing receptors sensitive to light intencity and colour
264
Bio: what controls and **monitors** body temperature in the body
The thermoregulatory center
265
Bio: what receptors does teh thermoregulatory center contain
Receptors that are **sensitive to the temperature of the blood**
266
Bio: what organ contains receptors that send signals to the thermoregulatory center in the brain
The skin contains temperature receptors that can send signals back to the thermoregulatory center in the brain
267
bio: what happens when the temperature in the body is too high
- The blood vessels dilate
- sweat is produced from the sweat glands
- both of these cause a transfer of energy from the skin to the environment
268
Bio: what happens if the blood temperature is too low
- the blood vessels constrict
- sweating stops
- skeletal muscles contract (skiver)
269
Bio: what are the properties of asexual production
- it involves only one parent and no fusion of gametes
- there is no mixing of genetic information, clones are created
- **only mitosis is involved**
270
bio: where does meiosis occur
Reproductive organs
271
Bio: what happens during cell division that forms gametes
- copies of genetic information are made
- the cell divides twice and each daughter cell has half of the normal genetic information (a single set of chromosomes)
- all gametes are genetically different from one another
272
Bio: when do gametes join and what does this do to the number of chromasones
During fertilisation, it restores the normal number of chromasones
273
Bio: what happens to the zygote after fertilisation
It divides by mitosis and thus the number of cells increases, as the embryo develops and the number of cells increases cells can begin to differentiate
274
Bio: what are the advantages of asexual reproduction
- only one parent needed
- more time and energy efficient as finding a mate is not necessary
- faster than sexual reproduction
- many identical offspring can be produced when conditions are favorable
275
Bio: are all organisms exclusive to either sexual or asexual reproduction
No, some organisms can do both sexual and asexual reproduction, depending on the conditions
276
Bio: what is an example of a protist that produces sexually and asexually
- malaria
- it reproduces **sexually** inside the mosquito
- it reproduces **asexually** in the human body
277
Bio: what is an example of a fungi that produces sexually and asexually
- many fungi do this
- they produce asexually by spores
- they produce sexually for variation
check
278
Bio: what is an example of a plant that can reproduce both sexually and asexually
- many plants do this
- they produce seeds sexually
- they used runners, such as strawberry plants, or bulb division such as daffodils, to reproduce asexually
279
Bio: what is it called when DnA is copied into mRnA
Transcription
280
Bio: what is attached to an TRNA when is bonds to a codon
An amino acid
281
Bio: dna unfolding during protien syntheses
The two strands of the DNA helix are unzipped by breaking of the weak Hydrogen bonds between base pairs
282
Bio: what are the 3 types of mutation
- addition (of a bace pair)
- subtraction (of a bace pair)
- replacement/substitution (of a bace pair)
283
Bio: what is the most damaging type of mutation
Addition and deletion because from the point of deletion and addition all of the subsequent amino acids change
284
Bio: what is the least damaging type of mutation
Substitution - least harmful as it only changes one amino acid
285
Bio: what are causes of mutation
- Ionising radiation
- chemical mutagens - such as some from cigarette smoke
286
Bio: how were living things traditionally classified
They were classified into groups depending on their structure and characteristics, in a system developed by **Carl Linnaeus**
287
Bio: what did linneauses system classify organisms into
- kingdom
- phylum
- class
- order
- family
-genus
- species
288
Bio: how are organisms named
They are named by the binomial system of genus and species
289
Bio: after the linnean system what happened that led to other models of classification
- the evidence of internal structures became more developed
- the understanding of biochemical processes progressed
- improvements in microscopes
290
Bio: what is the current system of classification of organisms and why did it come about
Due to evidence available for chemical analysis there is now a 'three-domain system' developed by Carl Woese, in this system organisms are divided into:
- Archaea (privative bacteria usually living in extreme environments)
- bacteria (true bacteria)
- eukaryote (which includes protists, fungi, plants and animals)
291
Bio: what are archaea
They are primative bacteria usually living in extreme environments
292
Bio: what are bacteria (in the 3 domain system)
They are true bacteria
293
Bio: what are eukaryota
They are protists, fungi, plants and animals
294
Bio: what is a method used by scientists to show how they believe organisms are related
Evolutionary trees
295
Bio: what do evolutionary trees use (types of evidence)
Current classification data for living organisms and fossil data for extinct organisms
296
Bio: why do bacteria evolve rapidly
Because they reproduce at a fast rate
297
Bio: what do mutations of bacterial pathogens produce
They produce **new strains**
298
Bio: how do we reduce that rate of development of antibiotics resistant strains
- doctors not prescribing antibiotics improperly, such as treating non-serious viral infections
- patients should complete their course of antibiotics so all bacteria are killed and none survive to mutate and form resistant strains
- the agricultural use of antibiotics should be restricted
299
Bio: why is the development of new antibiotics not likely to keep up with the development of resistant strains
Because the development of new antibiotics is costly and slow
300
Bio: what were many forms of early life and what relevance does this have on own knowledge of how life began on earth
They were soft-bodied, this means that they would have left few traces behind, the traces that may have been left may have been destroyed by geological activity
301
Bio: what do we learn from fossils
How much or how little different organisms have changed as life developed on earth
302
Bio: what 3 things does homeostasis control
- blood glucose control
- body temp
- water levels
303
Bio: what hormone does the pancreas produce
insulin
304
Bio: what does the pituitary gland do
It secretes several hormones into the blood in response to body conditions
305
Bio: what do pituitary gland hormones cause
They act on other glands to stimulate other hormones to be released to bring about effects
306
Bio: where is the pituitary gland
307
Bio: where is the pancreas
308
Bio: where is the thyroid
309
Bio: where is the adrenal gland
310
Bio: what happens when blood sugar is too low
The pancreas releases glucagon which stimulates glycogen deposits in the liver to become glucose
311
Bio: what is lost through sweat
- water
- ions
- urea
312
Bio: how is the loss of water ions and urea through the skin controled
It is not!!!!!!!!
313
Bio: what does the digestion of proteins in the digestive system result in
An excess of amino acids which need to be excreted safely
314
Bio: how are amino acids turned into urea
In the **liver** acids are deaminated to form ammonia, it is toxic and so is immediately converted into urea for safe excretion
315
Bio: when is adrenaine relased
Times of fear and stress
316
Bio: what hormones are included in fertility drugs
- FSH
- LH
317
Bio: what is the process for IVF
- FSH and LH are given to a mother to stimulate the maturation of several eggs
- the eggs are collected from the mother and fertilised by sperm from the father in the lab
- these fertilised eggs develop into embryos
- at the stage when they are tiny balls of cells, one or 2 embryos are inserted into the mothers uterus (womb)
318
Bio: what are the drawbacks of fertility treatment
- it is very emotionally and physically stressful
- The success rates are not high
- it can lead to multiple births which are a risk to both the babies and the mother
319
Bio: during puberty what characteristics do hormones cause
Secondary sex characteristics
320
Bio: where is oestrogen produced
At the ovary
321
Bio: how often are eggs released
28 days
322
Bio: what is the main male and female reproductive hormone
- male - testosterone
- female - oestrogen
323
Bio: what does testosterone stimulate the production of
sperm
324
bio: what does FSH do
Stimulates the maturation of the egg
325
Bio: what stimulates the release of the egg
LH
326
Bio: what 2 hormones are involved in maintaining the uterus lining
- oestrogen
- progesterone
327
Bio: who developed the 3 domane system
Carl woese
328
Bio: where is DNA found
In the chromasones
329
Bio: how many strands make up DNA
2
330
Bio: what have scientists done to the whole human genome
It has all been studied
331
Bio: what is the process of studying the human genome important for
- it can be useful for searching for genes linked to types of disease
- for understanding the treatment of inherited disorders
- can be used to trace human migration patterns in the past
332
Bio: what does the order of bases control
The order in which amino acids are assembled to produce a particular protein
333
Bio: what sub-cellular structure makes proteins
ribsomes
334
Bio: how often do mutations occur and what do most mutations do
continuously, most mutations do not alter the protein or only slightly so that its appearance or function is not changed
335
Bio: what can happen when a mutation alters a protein to make it have a different shape
An enzyme may no longer fit the substrate binding sit or a structural protein may loose its strength
336
Bio: what can a mutation in non-coding DNA do
They may affect how genes are expressed
337
Bio: what causes most characteristics
They are a result of multiple genes interacting
338
Bio: what is genetic engineering
It is a process which involves modifying the genome of an organism by introducing a gene from another organism to give it a desired characteristic
339
Bio: how have plant crops been genetically engineered
They have been engineered to be resistant to diseases and to produce bigger better fruits
340
Bio: how have bacteria been genetically engineered
They have been engineered to produce human insulin
341
Bio: what types of modifications do GM crops include
- they can be resistant to insect attack or herbicides
- they can generally show increased yields
342
Bio: what are some concerns about GM crops
They could have an effect on the proportions of flowers and insects and some people feel the effects of eating GM crops on human health have not been fully explored
343
Bio: in relation to genetic engineering what is modern medical research exploring
How to overcome some inherited disorders
344
Bio: what is the process for genetic engineering
1. Enzymes isolate the required gene and the gene is inserted into a vector, usually a bacteria plasmid or virus
2. The vector is used to insert the gene into required cells
3. Genes are transferred to the cells of animals , plants or microorganisms at an early stage of development so that they develop with the required characteristics.
345
Bio: what are some risks of genetic engineering
- they could cause allergic reactions
- they could be harmful, toxins from crops could get into foods
- pollen could be toxic and harm insects that transfer it
- ethical concerns and prices
346
bio: how many pairs of chromasones control the characteristics of humans and what do the others do
22 chromasones control characteristics and they others determine sex
349
Bio: how much genetic variation is there usually within a population of a species
There is usually extensive variation within a population of a species
350
Bio: how often do mutations occur
continuously
351
Bio: how do variations occur and what affect on the phenotype do most have
Most variations occur from mutations and most of them do not affect the phenotype, some influence the phenotype, very few determine the phenotype
352
Bio: how often do mutations affect the phenotype
Not very often
353
Bio: if a mutation leads to variation in the phenotype, what can this lead to
a relatively rapid change in the species
354
Bio: what is evolution
It is a change in the inherited characteristics of a population over time through a process of natural selection, which may result in the formation of a new species
355
Bio: what are the 2 pieces of evidence that you must know for evolution
- bacterial resistance
- fossils
356
Bio: what did gregor mendel do
In the mid 19th century he carried out breeding experiments on plants, one of his observations was that inheritance of each characteristic is determined by units that are passed on to descendants unchanged
357
Bio: when was the behaviour of chromasones during cell growth observed
Late 19th century
358
Bio: when was it observed that chromosomes and Mendel's units behaved in a similar way
20th century
359
Bio: when was the structure of DNA determined
The mid 20th century
360
Bio: why were Mendel's discoveries not recognised until after his death
- when he presented his work to other scientists he did not communicate it well so they did not really understand it
- it was published in a scientific journal that was not well known so not many people read it.
361
Bio: whose work led to gene theory
**many scientists**
362
Bio: when and is what book did Darwin publish his ideas
- 1859
- on the origin of species
363
Bio: why was the theory of evolution only gradually accepted
- the theory challenged the idea that god made all animals and plants that live on earth
- there was insufficient evidence at the time the theory was published to convince many scientists
- the mechanism of inheritance and variation was not known until 50 years after the theory was discovered
364
Bio: what is an embryo transplant
It is where cells from a developing animal embryo before they become specialised, then transplanting the identical embryos into host mothers
365
Bio: what are the 2 methods for plant cloning
- cuttings
- tissue cultures
366
Bio: how are plants cloned through cuttings
It is an older method where gardeners produce many identical new paints from a parent plant by taking a cutting of the plant check
367
Bio: how are plants cloned by tissue cultures
Using small groups of cells from a plant to grow identical new plants
368
Bio: why are tissue culture clones of plants important
It is important for preserving rare plant species or commercially in nurseries
369
Bio: how does one species form 2
If 2 populations of one species become so different in phenotype that they can no longer interbreed to produce fertile offspring they have formed 2 new species
370
Bio: what is selective breeding also known as
Artificial selection
371
Bio: how long ago did we begin doing selective breeding and what on
1000s of years ago, on food crops, wild plants and domesticated animals
372
Bio: what are characteristics that organisms are selectively bred for
- disease resistance in food crops
- animals that produce more meat or milk
- domestic dogs with a more gentile nature
- large unusual flowers
373
Bio: what negative thing can selective breeding lead to
Inbreeding, this is where some breeds are particularly prone to disease of inherited defects
374
Bio: who created the theory of speciation
Alfred Wallace
375
Bio: what is Alfred Wallace best known for
He worked worldwide and contributed much to evolutionary theory, he worked on the carning colouration of animals and he is known also for his theory of speciation
376
Bio: has the theory of speciation advanced sinse Wallace and why
Yes because more evidence was discovered over time
377
Bio: what can effectors be
- muscles
- glands secreting hormones
378
Bio: where are the ovaries
379
Bio: in comparison to the central nervous system what are the properties of hormones
- the effects are slower
- they act for longer
380
Bio: what are some causes of environmental variation
- amount of water
- tattoos
- climate, diet, accidents, culture and lifestyle. For example, if you eat too much you will become heavier, and if you eat too little you will become lighter
381
Bio: what type of organisms are saprophytic
- fungi
- bacteria
Check
382
Bio: where does amalayse act
Mount and small intestine
383
bio: what is eutrophication
it is a type of water pollution caused by the addition of fertiliser or sewage
384
bio: what is the process for eutrophication
1. excessive organic waste such as fertilisers are added by being washed into the area by rainwater or by some other means
2. algae overgrows
3. no light for plants sitting low in the water so they die and are decomposed reducing the O2 in the water by respiration
4. reduced O2 in the water, aquatic animals die
385
bio: what are the properties of FSH
- it is produced by the pituitary glands
- it causes egg to mature
- released on day 14
- stimulates the ovaries to produce oestrogen
386
bio: what are the properties of oestrogen
- it is produced by the ovaries
- stimulates the uterine lining to grow
- inhibits the release of FSH
- stimulates the release of LH
387
bio: what are the properties of LH
- produced by the pituitary glands
- stimulates the release of the egg
- day 14
388
bio: what are the properties of progesterone
- produced in the ovaries
- maintains uterus lining
- increases in stage 4
- progesterone levels drop then the cycle repeats
389
bio: if the egg is fertilised what happens to progesterone
the corpus luteum does not break down and continues to produce progesterone
390
bio: how can **type one** diabetes be treated
it can be treated by monitoring the blood sugar levels and injecting human insulin throughout the day (particularly after meals)
391
bio: how can **type 2** diabetes be treated
by maintaining a low carb diet and regular exercise to reduce the need for insulin
392
Bio: what happens when an enzyme denatures
Heat or something else (such as acidity) causes the enzyme to change shape and so they substrate is no longer complimentary to the active site
393
Bio: pregnancy test monoclonal antibodies link
394
Bio: how can monoclonal antibodies be used for diagnosis
The antibodies are specific to antigens, such as those on blood clots or cancer cells, the monoclonal antibodies have markers that allow doctors to find their location.
395
Bio: how can monoclonal antibodies be used for measuring and monitoring
They can be used to detect not only the presence of a chemical or the pathogen but the quantity. For example to drug test athletes and to screen for hiv.
396
Bio: how can monoclonal antibodies be used for research
They can have a fluorescent dye to detect specific molecules in a cell or tissue
397
Bio: how can monoclonal antibodies be used for testing
- cancer can be difficult to treat, monoclonal antibodies can be used in many ways to treat cancer
1. Use for the monoclonal antibodies to trigger immune cells to destroy them
2. They can be used to block receptors which stops them from growing and dividing
3. Carrying toxic drugs or radioactive substances for radiotherapy, to the site of the tumor
398
Bio: how can monoclonal antibodies be used in pregnancy tests
- the monoclonal antibodies are specific to a hormone produced in pregnancy
- the hormone is called human chronic gonadotropin (HCG)
- they will bind to the hormone if present and produce a colour change
399
Bio: what did the observation that units and chromasones behaved in a similar way lead to
The idea that units, now called genes were located in the chromasomes
400
bio: what does the graph of hormone levels over time look like (mensural cycle)
401
Bio: are dominant genes upper or lower case
Upper case
402
Bio: if gene B encodes for brown eye and b for blue eyes what colour eyes will a person with Bb have? What about bb?
Bb = brown eyes
bb = blue eyes
