6-8 mark questions

Question 1

describe the process of the menstrual cycle

Answer 1

day 0-4: The lining of the uterus breaks down
day 4-14: The uterus starts to build ``

Question 2

how does euriphication work

Question 3

how are hormones used in agriculture

Question 4

compare prokaryotic and eukaryotic organisims

Answer 4

.they are both bounded by a cell membrane
.they both have ribosomes (though they are different sizes)
.prokaryotic organisms have a cell wall. Cell walls are also found in the eukaryotic organisms, plants and fungi
.prokaryotic organisms are much smaller in size than eukaryotic organisms
the genetic material of prokaryotic cells is a single loop of DNA that lies in the cytoplasm - in eukaryotic organisms, it is in the nucleus
prokaryotic cells have additional DNA .DNA in a ring called a plasmid (plasmids are very rarely found in eukaryotic organisms)

Question 5

what are ways that pathogens/disease can be transmitted

Answer 5

. though bodily fluids ( blood, seamen, saliva ect…)
.through cuts in the skin
.through vectors
.in water
.in air
.coughs or sneezes

Question 6

what are some ways to prevent pathogens

Answer 6

.condoms
.sterelize or disinfect surfaces
.getting vacinations
.destroying/killing vectors
.preparing food and drink properly
.sterilizing water with UV rays

Question 6

describe the process of monoclonal antibodies

six marks

Answer 6

1) an antigen is injected into a mouse

2) the mouse naturally produces lymphocytes to fight off the pathogen

3) these produce antibodies specific to the antigen

4) spleen cells containing lymphocytes are removed during a small operation
the spleen cells are fused with cancerous white blood cells called myeloma cells

5)these form hybridoma cells called which divide indefinitely

6)they produce millions of monoclonal antibodies specific to the original antigen which are now extractable to be used for vacinations

Question 7

how does the body prevent pathogens from makeing us ill

Answer 7

.your skin acts as a physical barrier against pathogen

.your nose has hairs within them which act as a physical barrier to infection

.mucus is produced by goblet cells in your nose, throat and trachea

.mucus/saliva/tears contain lyozyme a natrual disinfectant

. goblet cells in the throat secrete mucus which helps protect the lining of the bronchus

.stomach acid kills pathogens

Question 8

describe the processes of the nitrogen cycle

Answer 8

• Bacteria convert nitrogen gas in the atmosphere into ammonium via nitrogen fixation

-other bacteria found in the root nodule’s or soil then convert the ammonium ions into nitrites and then nitrates through the process of nitrification

-the nitrates are absorbed by the roots of the plant, which is then eaten by an animal.

-after the plants of animals die bacteria turn the DNA and protein into ammonium through decomposition. After that the process repeats from there

-some nitrogen gas is not absorbed by the plants, instead bacteria convert the nitrates straight into nitrogen gas (denitrification) that goes back into the atmosphere

Question 10

why are the effects of smoking on the body give 3 points and explain

Answer 10

bronchioles and alveoli are damaged/destroyed
lungs become inflamed and mucus builds up
breathing is impaired, and the patient does not receive sufficient oxygen

lung cancer is another effect owing to chemical carcinogens in cigarette smoke
cells divide uncontrollably and invade other parts of the body, forming secondary tumours - lung cancer is usually fatal

in pregnant women, smoking increases the risk of miscarriage, reduced birthweight of the baby, and respiratory disease in the child/later life

Question 11

compare transport systems in animals to plant transport systems

Answer 11

transport in animals is in blood vessels, while in plants it is in the xylem and phloem

blood is pumped around the body by a heart in most/many animals - in plants, the force for xylem transport is evaporation of water from the leaves, while in the phloem it is transported in sieve tubes using energy from respiration
plants have two systems, and transport is in several directions, while in animals, there is a one-way flow

in animals, different substances are transported in the same blood system, while in plants, the two systems transport different substances