Random Flashcards
1
Q
How is genetic polymorphism maintained in different species
A
- diff phenotype have selective advantage in diff habitat
- habitat vary seasonally
- predators therefore vary
2
Q
Convergent evolution
A
Development of structures from different origin not sharing common ancestors adapted to carry out similar functions
3
Q
How protein available to muscles of herbivores
A
- pepsin in stomach hydrolyse p bonds in pp
- trypsin produced by pancreas to break pp to shorter
- endo and exo
- amino acids absorbed into blood by villi and taken to muscle cells
4
Q
How wall of arteriole reduce blood flow to capillary network
A
- contracts
- vasoconstriction of lumen
5
Q
Why are there high stomata conc in low CO2 levels
A
- stomata open to allow CO2 to diffuse in for Ps
- less to reduce water loss
6
Q
Explain how active transport of sodium ions out of epithelium cell results in passage of glucose into blood stream
A
- lowers Na+ conc in epithelial cells which creates a conc gradient for Na+
- Na+ and glucose enter cell by cotransport
- increased glucose concentration in cell creates a diffusion gradient so that glucose can enter the blood by facilitated diffusion
7
Q
Impact of ABA
A
- closes stomata
- decreases water loss
- prevent wilting
8
Q
Why does waterlogged soil result in a reduction of root pressure
A
- less O2 for respiration
- less ATP produced
- less active transport of minerals into root to lower water potential
- less water into xylem by osmosis so less pressure generated
