genetics and modern evolutionary synthesis

Question 1

compare and contrast blending and particulate inheritance

Answer 1

blending inheritance (darwin) = phenotypes in offspring are average/blend of their two parents.
panagenesis - all parts of body produces particles of hereditary information

Gregor Mendel is famous for discovering “particulate inheritance” or the idea that hereditary elements are passed on in discrete units rather than “blended” together at each new generation.

Question 2

core ideas in weisman’s germ plasm theory

Answer 2

Separation of Germ and Somatic Cells:
Weismann proposed that heritable information is transmitted exclusively through germ cells (gametes) in the gonads. Somatic cells (the rest of the body) do not contribute to heredity.

Direction of Information Flow:
The flow of genetic information is unidirectional: from germ cells to somatic cells, but not the reverse. This means that changes or adaptations occurring in somatic cells during an organism’s life do not affect the genetic material passed on to offspring.

Immutability of Germ Plasm:
Germ cells, or the germ plasm, are viewed as potentially immortal, while somatic cells are temporary and expendable, serving primarily to support the organism’s life functions. germ cells pass on the genetic information. .

Question 3

Mendel’s law of inheritance

Answer 3

genes - specific sequence of DNA
locus - broader term like a specific location/sequence of DNA on chromosome. It could have genes or not

law of dominance - if two alleles at locus differ, then the dominant shows. P x w = Pw (purple)

law of segregation - same copies of same alleles (homozygote), and different copies (heterozygote). during gamete formation, the two alleles for each trait separate so that each gamete carries only one allele, resulting in offspring that inherit one allele from each parent.

law of independent assortment - says that different traits are passed on to offspring independently, so the way one trait is inherited doesn’t affect how another trait is inherited.

Question 4

why inheritance is complex

Answer 4

there are different types of dominance
complete dominance - if red is dominant, and white is recessive.
Then offspring would be red (or white)

incomplete dominance - red and white would make it pink. (Cr x Cw
would make it CrCw)

codominance - both parts show, like in blood type

alleles don’t segregate independently, it means that the inheritance of one allele at a locus (a specific gene location) can affect the inheritance of another allele at a different locus. This contrasts with the usual expectation that alleles for different traits assort independently during gamete formation.