Cross breeding and F1 hybrids

Question 1

Crossbreeding

Answer 1

In animals, crossbreeds are produced when individuals from different breeds reproduce.
Given the problems associated with inbreeding new alleles tend to be introduced into populations by crossbreeding with a strain exhibiting a different but desired genotype.
Breeders often deliberately maintain stock by crossbreeding regularly.

Question 2

What do crossbred population show -

Answer 2

Improved characteristics - hybrid vigour.

Question 3

What will the crossbred be used for

Answer 3

Food mostly as the offspring of that generation could be unsuitable since they will be very varied

Question 4

F1 hybrids

Answer 4

In plants. an F1 hybrid is an individual resulting from a cross between two genetically dissimilar parents of the same species.

Question 5

The F1 hybrid will be

Answer 5

A relatively uniform heterozygous crop

Question 6

Hybrid vigour

Answer 6

F1 generation whose members display increased vigour – they may have increased disease resistance or growth rate.

Question 7

F2 generation

Answer 7

Will be too varied and unsuitable for use as they would lack desired characteristics

Question 8

Why may parent breeds be maintained (parents of F1)

Answer 8

to produce more crossbred animals showing the improved

characteristic