BIOLOGY PAPER 1BR 2023 JAN Flashcards
1
Q
Why composition of air in exhaled air is different than in alveoli
A
Gas exchange occurs in alveoli only
Exhaled air is mixture alveolar air and inhaled air.
2
Q
What happens if plants have less chloroplast
A
- chloroplast absorb in light for plants
- Less light = less photosynthesis
- less photosynthesis = less glucose
- less glucose = less respiration
3
Q
Why not all biomass is transferred
A
- loss to respiration/heat/movement
- loss to excretion
- Some decompose
-Some is not digested - not all organism is eated
4
Q
Test for protein
A
-add biuret
- becomes purple/blue
5
Q
How plant is adapted for wind pollination
A
- petal is small and not coloured
- no nectar
- pollen is light so easily carried
- anther hang outside so blow pollen in wind
- feathery stiga to catch pollen
6
Q
How cross pollination can make plants adapted to change in environment
A
- Cross pollination produces more genetic variation
- So natural selection can occur
- some plants will be more adaptable
7
Q
Difference between meiosis and mitosis
A
-
8
Q
Why producing plant asexually is advantage for commercial grower
A
- plants genetically identical
- Have same characteristics
- Can be produced at any time
- Higher yield
9
Q
Reflex arc
A
- receptor receive impulses
- impulse move along sensory neurone to CNS
- neutransmiters across synapse
- motor neurone to affector
- muscle contracts
10
Q
Chemical equations for photosynthesis
A
C6H12O6 + 6CO2 -> 6H2O + 6O2
11
Q
How students could ensure result of investigation is reliable
A
- repeat
- calculate average
- remove anomaly
12
Q
Genetic modification protease enzymes
A
- restriction enzyme use to cut protease gene
- same restriction enzymes cut plasmid
- Gene and plasmid have same sticky ends
- ## ligase combine plasmid and gene forming recombinant plasmid
