T5

Question 1

complex traits/ quantitative differ from simple/mendelian traits

Answer 1

many traits that vary along a more continuous scale rather than ‘either-or’ that is seen in mendelian traits

• this will show a continuous trait distribution, seen in human height
• normally due to polygenic inheritance where many genes have small effects
• genes and environment can have an effect

Question 2

determining whether the genes or environment has a bigger impact to see the relative importance

Answer 2

need to determine how faithful the character is to being inherited
- we use heritability = Va / Vp

Question 3

estimating h2 using parent offspring regression

Answer 3

when parent trait on x axis and offspring trait on y axis, form a graph to look at the trait

from this calculate the gradient as that is showing the simiailirty between parent and offspring (y2-y1) and the variance in parental trait (x2-x1)

2x slope = (VA/VP) = h2

Question 4

intrepting the h2 regression line

Answer 4

the steeper the slope, the more important the genes are in determining the variation in a character
- variation and the trait is mostly genetic so will be passed on to offspring

figuring out heritability allows us to determine if worth selecting for growth/food/livestock

Question 5

hertiability and evolution

Answer 5

the higher the heritability of a trait, the faster the evolution of a trait because more likely that more offspring will have the the trait

low heritability means that trait can not be easily identified so less evolution of trait