Biology Assessment two

Question 1

What is a light microscope?

Answer 1

• uses light rays
• £100
• used in schools
• can see structures such as nucleus.

Question 2

What is an electron microscope?

Answer 2

• can see subcellular structures. (chloroplast and mitochondrion)
• expensive and not portable
• can be millions of pounds.

Question 3

How do you work out magnification?

Answer 3

Magnification= size of image/ real size of the object.

Question 4

Magnification of a light microscope?

Answer 4

1500 X 200NM res.

Question 5

Magnification of electron microscope?

Answer 5

2 million. 0.2nm res.

Question 6

What is diffusion?

Answer 6

Particles moving from a high to low concentration.

Question 7

Examples of where diffusion takes place?

Answer 7

Diffusion can occur in: Air – smells from perfume etc.
Solution – tea from a tea bag, dye in water etc.
Through membranes – small intestines, blood cells et

Question 8

How does diffusion happen in the small intestines?

Answer 8

Digested food moves from the small intestine to blood in capillary of villous.

Question 9

How does diffusion happen in the lungs?

Answer 9

Oxygen particles move from the alveolar air space to the blood circulating around the lungs.

Question 10

How does diffusion happen in the kidneys?

Answer 10

Urea cells move from cells to the blood plasma.

Question 11

What is meant by active transport?

Answer 11

Moves substances from a more dilute solution to a more concentrated solution against a concentration gradient.

Question 12

Where is the energy for active transport provided from?

Answer 12

Respiration.

Question 13

Give some examples of where active transport happens?

Answer 13

In root hair cells, the gut and also for respiration

Question 14

How does active transport happen in the gut?

Answer 14

glucose molecules are absorbed from lower concentrations in the gut into the blood which has a higher glucose concentration.

Question 15

How does active transport happen in the root hair cell?

Answer 15

The minerals are at a higher concentration in the root hair cell than soil. Minerals move against gradient.

Question 16

What is meant by digestion?

Answer 16

Where large insoluble molecules are broken down into smaller soluble ones that can be absorbed into the bloodstream. Happens in gut, reliant on enzymes.

Question 17

Digestion simplified is?

Answer 17

Different organs working together to digest and absorb food.

Question 18

Where is amylase released and what does it breakdown?

Answer 18

• released in the salivary glands and pancreas.

- breaks down carbs into simple sugars.

Question 19

Where is protease released and what does it breakdown?

Answer 19

• released in stomach and pancreas.

- breaks down proteins into amino acids.

Question 20

Where is lipase released and what does it breakdown?

Answer 20

• released in pancreas.

- breaks down lipids into fatty acids and glycerol.

Question 21

What must new drugs be tested for?

Answer 21

Toxicity, efficacy and dosage.

Question 22

What must preclinical tests be carried out on?

Answer 22

Cells, tissue and live animals.

Question 23

What are the stages of a clinical trial?

Answer 23

• healthy volunteers check no side affects.
• small number of patients on low dose
• larger amounts with different dosages.
• double blind trials.

Question 24

What is a double blind trial?

Answer 24

• making sure it is actually drug and not placebo affect.
• done computerised.
• nobody knows who had the placebo until end of trial.
• placebo is often the OG medicine the patient was already taking.

Question 25

What are some adaptations of the small intestine?

Answer 25

• villi increasing surface area
• villi have good blood supply maintains conc. gradient.
• membranes are thin so short diffusion distance.

Question 26

What are some adaptations of the lungs?

Answer 26

• air sacs called alveoli increase SA
• good blood supply maintains conc. gradient
• membranes are thin so short diffusion distance.

Question 27

Explain the importance of maintaining the concentration gradient in diffusion.

Answer 27

-The greater the difference between the concentrations (next to each other).
the faster the rate of diffusion occurs
- If the concentrations are the same there is no net diffusion.

Question 28

Describe the adaptations for transport in cells in animals.

Answer 28

• Small intestines: villi, increased surface area, good blood supply, membranes very thin
• Lungs: alveoli, increased surface area, good blood supply, membranes very thin

Question 29

Describe the adaptations for transport in cells in plants.

Answer 29

• Roots: root hair cells, increased surface area

- Leaves: large surface area, thin, xylem, phloem, stomata

Question 30

Drug trials are used to find out about dosage.

Why is this important both to the patient and economically?

Answer 30

• The dose is sufficient to treat the disease without being toxic
• The dose does not give undesirable side effects
• To use the least amount of drug to get the maximum effect to save costs

Question 31

In the initial stages of a clinical trial a low dose of the drug is used on healthy volunteers.
Suggest why this is not used with patients at this point.

Answer 31

-Patients need to take their prescribed drug which has been proved to be effective for their
condition - their condition may get worse if they are not taking this medication
-The new drug may have side effects that patients can’t cope with because they are unwell.