Variation and Sexual Reproduction Flashcards
disadvantages of sexual reproduction
50% of population cant produce offspring
Advantages of sexual reproduction
increases genetic variation
provides raw material required for adaptation
-increases survival under selection pressures
why is asexual reproduction a successful reproductive strategy
whole gametes can be passed from parent to offspring
How does asexual reproduction work
uses process of mitotic cell division
1 parent can produce colony daughter cells
when is maintaining the genome of a parent good in asexual reproduction
stable niche
disturbed habitats
what is vegetative cloning
asexual reproduction used in plants
What is Parthenogenesis and where is it more common
asexual reproduction from a female gamete WITHOUT fertilization
more common in cooler climates and regions of low parasite density
Advantages and DIsadvantages asexual reproduction
offspring produced more often and in larger amounts
not able to adapt easily to changes in environment
characteristics of homologous chromosomes
same size
same centromere position
same sequences of genes at the same loci
What is crossing over
when CHIASMATA forms at points of contact between NON SISTER chromatids
-DNA EXCHANGE OCCURS
-random
What is independent assortment
chromosome positioned independently of other pairs
Difference between homogametic and heterogametic cells
XX and XY
What is X chromosome inactivation
prevents double dos of gene products that can be harmful to cells
What are hermaphrodites
species that have both functioning male and female reproductive organs in each individual
-produce BOTH MALE AND FEMALE gametes
Sex determination examples
environment
size
competition
parasitic infection
