populations and ecosystems exam questions

Question 1

The student used the mark-release-recapture technique to estimate the size of thepopulation of sand lizards on an area of moorland. She collected 17 lizards and marked them before releasing them back into the same area. Later, she collected 20 lizards, 10 of which were marked.
(i) Give two conditions for results from mark-release-recapture investigations to be valid.
1. __________________________________________________________________The student used the mark-release-recapture technique to estimate the size of thepopulation of sand lizards on an area of moorland. She collected 17 lizards and marked them before releasing them back into the same area. Later, she collected 20 lizards, 10 of which were marked.
(i) Give two conditions for results from mark-release-recapture investigations to be valid.
1. __________________________________________________________________

Answer 1

-no births/deaths
-marking does not reduce surival chance/increase predation chance.
-emigration/immigration

Question 2

use the information to explain changes in oxygen uptake in the investigation (3)

Answer 2

–aerobic respiration
-increase in uptake of oxygen for growth
-anaerobic respiration/ethanol formed.

Question 3

sodium azide is a substance that inhibits the electron transport chain in respiration. the student repeated the investigation but added sodium azide after 4 hours.
Suggest how the addition would affect oxygen uptake and ethnaol production (3)

Answer 3

oxygen uptake is reduced
oxyen is the terminal electron acceptor
more ethanol produced.