Jan 2023 2B w Nitrogen cycle

Question 1

How Nephron absorbs glucose back into the blood from the filtrate

Answer 1

• selective absoprtion in proximal convoluted tubu
• active transport against concentration gradient

Question 2

How pituitary gland and the nephron cells will respond in a patient who is dehydrated

Answer 2

• if patient is dehydrated
• More ADH produced in Pituitary gland
• collecting duct become more permeable
• more water reabsorb in collecting duct
• less urine is produced

Question 3

What happened to pupil and circular muscles when light is bright

Answer 3

pupil dilate
Circular muscles contract

Question 4

Why predators have 2 forward facing eyes

Answer 4

• To be able to detect prey
• large area seen with both eyes
• better distance judgement

Question 5

Gene meaning

Answer 5

• section of DNA that codes for chain of amino acids

Question 6

Why there is greater variation in height than there is in hair colour

Answer 6

-height is polygenic (more than one genes control height)
-Height is environmental / diet
-

Question 7

How Cattle farmer can use selective breeding to get taller cows

Answer 7

• select cattle that are taller and mate them
• select offspring that are taller and mate them
• repeat through generation

Question 8

What’s micropropagation

Answer 8

method of plant propagation using extremely small pieces of plant tissue taken from a carefully chosen and prepared mother plant, and growing these under laboratory conditions to produce new plants.

Question 9

Why micropropagation was used to produce copies of genetically modified soya plant

Answer 9

• Fast
• No need to repeat genetic modification
  -Plants will be genetically identical
• No others to breed with

Question 10

How to make valid energy comparison experiment (burning food one)

Answer 10

• weigh bean to make sure it the same mass
• same volume of water
• Ignite the food under the test tube
• Ignite until it no longer burn
• measure temperature rise
  -repeat

Question 11

Safety apparatus when handling fire

Answer 11

• wear eye protection
• lab coat
• heat proof tile

Question 12

negative effect on an increase in CO2 gas

Answer 12

• more greenhouse gases
  -global warming
• climate change
• ice melting / rising sea level
  -animal extinction

Question 13

Decomposers bacteria

Answer 13

Breaks down protein and urea and turn them to ammonia

Question 14

Nitrifying bacteria

Answer 14

• Ammonium ions in decaying matter to nitrites then to nitrates

Question 15

Nitrogen fixing bacteria

Answer 15

Atmospheric N2 into N2 compound plants can use

Question 16

Denitrifying bacteria

Answer 16

• Nitrates into N2 gas

Question 17

How rabies vaccine prevents dogs from developing rabies

Answer 17

• inactive pathogens in vaccine
• inactive pathogens carry antigens
  -Lymphocytes recognize antigens
• lymphocytes produce antibodies
• memory cell produced and remains in blood
  -Produce faster antibodies if virus encountered again