Ocr 21st century Biology B7 revision quiz.

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To hold the bones together.

Name the four components of soil.

Inorganic particles such as sand, silt and clay.
Water with mineral ions.
Organic biomass.
Air.

Why is starch a better storage molecule than glucose?

Reply 21

Angelica.

It is insoluble in water, and therefore is not affected by the process of osmosis/ doesn't bloat the cells by osmosis.

A few off the specification... wonder if you guys could answer :P

1) Describe briefly one example of monitoring a person’s progress (a) during
treatment or fitness training (b) after this is complete;

2) Describe a set of exercises to treat one such injury.

Reply 22

redtortoise

A physio therapist may carry out tests before and after and during treatment to monitor progress.

Damaged knee lifting lower leg with out putting weight on it, small steps onto a box and then putting all weight on knee and stretching and bending it.

(ideas in context)
Name 3 invasive species mentioned in the text.
http://pdf.ocr.org.uk/download/prm/ocr_65106_prm_gcse_u223_rb.pdf?

Reply 23

swaine.

The ruddy duck, harlequin ladybirds and the japanese knotweed

What is biodiversity? (Refer to pre-release)

(edited 11 years ago)

Reply 24

redtortoise

The variety of organisms.

Explain the term biological control.

Reply 25

swaine.

Controlling a 'pest' by introducing a natural predator/ enemy of the pest.

Can someone help me, i dont understand why when blood passes through a capillary network plasma stops being squeezed out& the tissue fluid moves back into the capillaries? Help would be apreciated!

Reply 26

redtortoise

Only small molecules such as glucose oxygen and water are forced out. Waste molecules such as glucose then leave the cells and go back to the capillaries through the process of diffusion.

Japanese knotweed is difficult to remove because it can spread underground by putting out rhizomes. This is a form of cloning, explain what is ment by a clone?

Reply 27

swaine.

Clones are genetically identical organisms. They have the same genes and the same alleles of those genes.

In paragraph 3 it says "30 years ago there were 600 alien invasive species, it has increased by 75%" how many invasive species are they now?

Reply 28

redtortoise

600/100 x 175 = 1050

State two ways energy is lost in food chains.

Reply 29

swaine.

heat and animal waste

which three factors affect the rate of photosynthesis?

Reply 30

tonikarma

1. Amount of Light
2. Amount of CO2
3. Temperature

Describe capillary exchange?

Reply 31

swaine.

Tissue fluid contains all the raw materials carried by blood plasma. Theses chemicals diffuse out of the fluis and into the cells. Likewise the wast priducts from cells diffuse out into the tissue fluid then into the capillaries through a partially permeable membrane.
^^I think this is correct not 100% sure

What is the protein called which is found in red blood cells? (it binds oxygen)

Reply 32

Angelica.

Oxyhaemoglobin.

Describe how to make human insulin through genetic modification.

[If these questions come up, people will be sorry they didn't visit this thread earlier ;D]

Reply 33

swaine.

The gene for insulin is cut from a length of human DNA using enzymes, then the plasmid taken from a bacterial cell is cut by enzymes and the new gene is stuck in. the genetically modified plasmid is inserted back into the bacterial cell. the cell is then cultivated and soon there are millions of bacteria producing human insulin

What is fermentation?

Reply 34

Jamie King

Original post by swaine.

What is fermentation?

The chemical breakdown of a substance by bacteria, yeasts, or other microorganisms.

Explain what is meant by the term "antagonistic pairs" and give an example.

Reply 35

swaine.

and antagonistic pair are two muscles that work together, pulling in opposite directions -When one muscle in the pair contracts the joint moves in one direction, when the other muscle contracts it moves in the opposite direction.
For example: Biceps and triceps.

when do plants respire?

Reply 36

Catching22

24 hours a day

What is "oxygen debt"?

Reply 37

Ameenur

An oxygen deficiency caused by anaerobic respiration during intense or vigorous exercise. The 'debt' is the amount of oxygen needed by the body to oxidise the build up of lactic acid.

What 4 things make up the structure of bacteria

(edited 11 years ago)

Reply 38

Angelica.

[Assuming you mean the cell]
Cell Wall
Cell Membrane
Chromosomes
Plasmid
[Cytoplasm]

Give an ethical, economical and social view of Genetic Modification (either for human insulin or for disease resistant crops).

Reply 39

redtortoise

Its is wrong to try and change genes it is acting god, Its its cheaper to make products such as insulin, IT could help people in need i.e producing insulin for veggies.

Name symptoms of sickle cell aneamia.