artificial selection Flashcards
1
Q
artificial selection
A
- selecting and breeding organisms with desirable characteristics
- guided by humans based on understanding genetics and reproduction
2
Q
differences between natural and artificial selection
A
- process : artificial ; natural
- driven by : man ; nature
- rate of change : fast ; slow
- amount of variation : less ; much
- consequence : improved crops/livestock ; adaptation to environment
3
Q
importance of artificial selection
A
- domestication
- resistance
- improved quality and yield
- new strains
- hybrid crops
- adapt old crops
- special breeds
- enhance nutritional value
- develop useful characteristics
4
Q
inbreeding
A
- mating of closely related individuals
- self-fertilisation
- same parents
- select and continue particular characteristics
- less vigour and survival
5
Q
outbreeding
A
- mating of individuals not closely related
- greater change of survivability : tougher and more fertile
- heterozygous with undesirable traits
6
Q
artificial selection in domesticated animals
A
- canis familiaris (dog)
- 78 chromosomes and large variability
- canis lupus ancestor
- behavioural traits
- structural traits : hunting ; affection
7
Q
artificial selection in crop plants
A
- domestication : wild plants resulted in phenotypic changes
- new varieties
- dependant on human preservation
- classical plant breeding : deliberate interbreeding of closely or distantly related individuals
- modern plant breeding : genetic engineering ; mutagenesis (chemicals/radiation) ; embryo rescue (rescue embryos from seeds) ; polyploidy
8
Q
artificial selection in crops by domestication
A
- maize
- teosinte (wild grass) to maize
- remarkable genetic variation and some artificial breeding
- desirable features planted
- increase frequency of desired alleles
9
Q
some characteristics that were selected
A
- reduced covering of kernel
- retention of kernels on the cob
- erect habit with a single stalk
- larger ear structures
