Topic 1-2

Question 1

what is a major problem with the pangenesis theory?

Answer 1

if a parent lost a limb before conceiving, what would this mean for the offspring?

Question 2

what is Lamarckian inheritance?

Answer 2

the idea that traits are acquired over a person’s lifetime (such as proficiency with an instrument) and can be passed down to offspring

Question 3

what is pangenesis?

Answer 3

the early idea that each part of the body contains genetic information for that particular part, and specific particles (gemmules) carry that specific information to reproductive organs

Question 4

what is a major problem with Lamarckian inheritance?

Answer 4

underestimated the influence of early development and environment on acquired traits

Question 5

what is the idea of preformationism?

Answer 5

inside the egg or sperm exists a fully formed miniature adult (homunculus) which enlarges over the course of development, so offspring are genetically solely of the mother or father

Question 6

what is the problem with preformationism?

Answer 6

clashes with observations that individuals possess a mixture of traits from both parents

Question 7

what is the idea of blending inheritance?

Answer 7

each traits of offspring are a blend/mixture of parental traits

Question 8

what is Weissmann’s Germ-plasm Theory?

Answer 8

cells in reproductive organs carry a complete set of genetic information that is passed to the egg and sperm

Question 9

what were the key ideas of Darwin’s theory of natural selection?

Answer 9

• variation of traits within the population
• traits are inherited
• offspring with traits that increase their probability of survival survive to reproduce

Question 10

discovered the basic principles of heredity by examining pea plants

Answer 10

Gregor Mendel

Question 11

Gregor Mendel reasoned that each plant obtained _______ of something that resulted in a particular trait

Answer 11

two copies, one from the ‘mother’ and one from the ‘father’

Question 12

what is the law of independent segregation?

Answer 12

each individual carries two copies of an inherited trait which segregate equally in the following generation

Question 13

what is the law of independent assortment?

Answer 13

different inherited traits sort independently of one another

Question 14

what is the law of dominance?

Answer 14

for a trait, one allele is dominant and appears in a 3:1 ratio (dominant and recessive genes)

Question 15

• all life is composed of cells
• the cell is the fundamental unit of structure and function in living organisms
• cells arise only from pre-existing cells
  these are all a part of:

Answer 15

Schleiden and Schwann’s unified cells theory

Question 16

who was the first person to publish on the movement of chromosomes during cell division?

Answer 16

Walther Flemming

Question 17

what is the Boveri-Sutton chromosome theory?

Answer 17

heritable units are located on chromosomes

Question 18

Thomas Hunt Morgan discovered what about drosophilia flies in his lab?

Answer 18

white eyes are a sex linked characteristic

Question 19

Morgan’s research about sex linked characteristics, which linked traits to chromosomes, confirmed:

Answer 19

• Mendel’s laws of inheritance
• Boveri-Sutton chromosomal theory