Year 11

Question 1

Drug

Answer 1

Any substance that when taken into the body modifies or effects chemical reactions in the body

Question 2

Effect on bacteria of antibiotics

Answer 2

Disrupt the production of the cell wall hence don’t effect humans as our cells don’t have a cell wall

Question 3

Effect of antibiotics on Viruses

Answer 3

No effect as virus e have totally different characteristics and genetic material to bacteria and no cell walls

Question 4

Effects of alcohol and abuse of heroine

Answer 4

Depression as they are powerful depressant drugs
Effect on reaction times and self control
Addiction and withdrawal symptoms
Negative social implications such as crime

Question 5

Effect of alcohol abuse

Answer 5

Liver damage and cirossis

Question 6

Effects of smoking

Answer 6

COPD
Lung cancer
Coronary heart disease

Question 7

Site of breakdown of alcohol and other toxins

Answer 7

The liver

Question 8

Advantages and disadvantages of aesexual reproduction in the wild

Answer 8

No need to find other organisms
Favourable genes passed on
All offspring find themselves in a favourable environment
However little variation minimising natural selection
Overcrowding same plant competing for the same resource
Lack of natural immunity to diseases

Question 9

Advantages and disadvantages of aesexual reproduction in a crop

Answer 9

Able to grow a consistent crop

However this crop is more susceptible to disease

Question 10

Advantages of sexual reproduction in the wild

Answer 10

Increased variation to form new traits
Resistance to disease
Seeds scattered over a wide distance
However seeds take longer to grown 
Many land in poor environments
Some variants will have a lower chance of survival

Question 11

Fertilisation

Answer 11

Fertilisation is the fusion of gamete nuclei

Question 12

Pollination

Answer 12

Transfer of pollen grains from the anther to the stigma

Question 13

Advantages of self pollination

Answer 13

Less reliance on pollinators

Question 14

Sequence of events from pollination to fertilisation

Answer 14

Pollen grain stimulated to grow a tube by chemicals on the stigma
Pollen tube grows down the style until it reaches the micropyle at the bottom of the ovary
There the two gamers fertilise and forms zygote

Question 15

Adaptions of wind pollinated plants

Answer 15

Produce large quantities of light smooth pollen
Anthers and stigmas hang outside the flower
Stigmas are feathery to increase surface area

Question 16

Adaptions of insect pollinated plants

Answer 16

Large petals
Nectaries
Dark lines on flower guide the answers to the nectar and pollen
Vivid colours

Question 17

Adaptive Features of a sperm

Answer 17

Flagellum mitochondria and enzymes in the acrosome

Question 18

Adaptive features of egg cells

Answer 18

Energy stores

Jelly coat that changes at fertilisation

Question 19

Fertilisation to implantation

Answer 19

Zygote divides by mitosis to form an embryo which is a ball of cells
This ball of cells implants into the wall of the uterus

Question 20

Function of the placenta

Answer 20

Responsible for maintenance and exchange during pregnancy

Question 21

Function of the umbilical chord

Answer 21

Link between the placenta and foetus, Carey’s nutrients and oxygen to the foetus and Carey’s bile urea and carbon dioxide away from the foetus

Question 22

Function of the amniotic sack

Answer 22

Contains the amniotic fluid and fully enclosed the foetus protecting it against pathogens

Question 23

Function of the amniotic fluid

Answer 23

Supports the baby and protects it from impacts

Question 24

Preparation for birth

Answer 24

Foetus moves into a head down position

Mucus plug of the cervix is released

Question 25

Processes involved in Labour and birth

Answer 25

``` Breaking of the amniotic sack Contractions of the muscles in the uterus wall Dilation of the cervix Passage through the vagina Tying and cutting of the umbilical chord Delivery of the afterbirth ```

Question 26

Hormones in contraception and fertility treatment

Answer 26

Contraception- progesterone and oestrogen | Fertility treatment FSH

Question 27

Artificial insemination

Answer 27

Sperm from a donor is injected at the top of the uterus

Question 28

IVF (In vitro fertilisation)

Answer 28

Ova are collected and mixed in semen multiplying zygotes are then introduced into the uterus and usually one or more of the zygotes develop

Question 29

Effect of HiV and AIDS

Answer 29

Decreased lymphocyte production and reduces ability to produce antibodies

Question 30

What is a gene

Answer 30

Length of DNA that codes for a protein

Question 31

How are proteins made

Answer 31

Gene coding for protein remains in the nucleus mRNA carry a copy of the gene to the cyctoplasm Mrna passes through ribosomes on rough endoplasmic reticulum Ribosomes assemble amino acids into protein molecules The order of amino acids is determined by the sequence of bases in the mRNA

Question 32

Stem cells

Answer 32

Unspecialised cells that divide by mitosis to produce daughter cells which can become specialised for specific functions

Question 33

Allele

Answer 33

Version of a gene

Question 34

Continuous variation

Answer 34

Results in a range of phenotype a between two extremes

Question 35

Gene mutation

Answer 35

Change in the base sequence f DNA this is how new alleles are formed

Question 36

Cause of sickle cell aenemia

Answer 36

Change in the base sequence of the gene which code for haemoglobin this results in abnormal haemoglobin and red blood cells which become sickle shaped in environments with less oxygen

Question 37

Symptoms of sickle cell

Answer 37

Loss of breath

Question 38

Unusual effect of sickle cell

Answer 38

Those who are heterozygous with sickle cell have a resistance to malaria this means that in some countries being a carrier of sickle cell is naturally selected Incidences of sickle cell are much higher in areas with malaria

Question 39

Process of natural selection

Answer 39

There is variation in populations Many offspring are produced There is competition for resources There is a struggle for survival Individuals who are better adapted are able to reproduce more than others They pass on favourable alleles to the next generation

Question 40

Process of selective breeding

Answer 40

Selection by humans of individuals with desirable features These individuals are crossed to produce the next generation Offspring are then selected for desirable features

Question 41

Energy loss down the tropic levels

Answer 41

Inefficient as most of the energy does not go to producing edible material the vast majority is lost due to respiration and other processes

Question 42

Population | Community

Answer 42

Group of organisms of one species living in the same area at the same time All of the populations of different species in an ecosystem

Question 43

Why are bacteria useful in biotechnology

Answer 43

Lack of ethical concerns Genetic code shared with all other organisms Fast growth rate Presence of plasmids

Question 44

Steps of genetic engineering in bacteria

Answer 44

Isolation of dna making up a human gene using restriction enzymes forming sticky ends. Cutting of bacterial plasmid with the same restriction enzyme forming complementary stick ends. Insertion of Human DNA into plasmid using DNA ligament. Insertion of plasmid into bacteria,replication of bacteria in a fermenter which make the human gene

Question 45

Issues with monoculture a and intensive livestock production

Answer 45

Natural balance of plants and animals is destroyed, potential that the variety of wildlife ends in the area

Question 46

Eutrophication

Answer 46

Increased availability of nitrates from fertilisers Increased growth of producers (algal bloom) Decomposition after death of producers which leads to high levels of aerobic respiration of producers Reduction in dissolved oxygen Death of organisms requiring oxygen

Question 47

Measures to reduce sulphur dioxide emissions

Answer 47

Desulphurisation plants Use if different fuels in power plants Filters on the top of plants

Question 48

Risk to a population if its size drops

Answer 48

Reduced variation due to size of gene pool