BIOLOGY CH 8

Question 1

What are the results after centrigue?

Answer 1

Pellet at the very bottom and supernatant

Question 2

Do all genes produce proteins as end products?

Answer 2

No. Some genes produce tRNA, rRNA, as well as other small nuclear RNA genes; these do not produce proteins

Question 3

What is classical dominance?

Answer 3

When one allele is dominant and another is recessive meaning that although there are 3 different genotypes, there are only 2 different phenotypes.

Question 4

In males, meiosis occurs in the ______ with haploid ______ as the end result; in females meiosis in the ______ produces _______ .

Answer 4

Testes; Spermatozoa; Ovaries; Ova

Question 5

Incomplete dominance

Answer 5

Pink flowers

Question 6

Codominance

Answer 6

Red and white flowers; blood type

Question 7

Pleitropism

Answer 7

One gene influences multiple phenotypes

Question 8

Polygenism

Answer 8

One phenotype is affected by many genes

Question 9

Epistasis

Answer 9

One gene expression is dependent on another gene’s

Question 10

Recessive lethal alleles

Answer 10

Mutant alleles can cause death of an organism when present in homozygous manner

Question 11

The failure of genes to display independent assortment is called ________ .

Answer 11

Linkage

Question 12

How do you calculate frequency of recombination?

Answer 12

Number of recombinants / Total number of offspring

Question 13

Gene pool

Answer 13

The sum total of all genetic information in a population

Question 14

Fitness

Answer 14

How successful an animal is in passing on its alleles to future generations. The way to have greater fitness is by having more offspring that pass on their alleles to future generations of the population

Question 15

Directional selection

Answer 15

When natural selection removes one extreme of a phenotype and over time the average moves closer to the other extreme

Question 16

Divergent selection

Answer 16

When natural selection removes the average of a phenotype causing the extremes to be more prevalent

Question 17

Stabilizing selection

Answer 17

When natural selection removes both extremes of a phenotype and over time the average phenotype becomes more prevalent

Question 18

Kin selection

Answer 18

Animals sacrificing themselves for the sake of the alleles they share with another individual

Question 19

Hybrid inviability

Answer 19

Hybrid offspring do not develop or mature normally, and normally die in the embryonic stage

Question 20

Hybrid sterility

Answer 20

A hybrid individual is born and develops normally, but does not produce normal gametes, and thus is incapable of breeding

Question 21

Hybrid breakdown

Answer 21

When two hybrids mate successfully to produce a hybrid offspring, but this second generation hybrid is somehow biologically defective

Question 22

Homologous structures

Answer 22

Physical features shared by two different species as a result of a common ancestor

Question 23

Analogous structures

Answer 23

Serve the same function in two different species, but not due to common ancestry

Question 24

Convergent evolution

Answer 24

Two different species evolve to look-alike (many analogous structures) due to similar selective pressures

Question 25

Divergent evolution

Answer 25

A form of evolution in which the same organism is placed into different environments with different selection pressures. This causes the organisms to evolve differently; to diverge from their common ancestor. The resulting (new) species may share structural similarity

Question 26

It is thought that the early atmosphere was a _________ environment.

Answer 26

Reducing environment

Question 27

Abiotic synthesis

Answer 27

Spontaneous polymerization catalyzed by metal ions

Question 28

Proteinoids

Answer 28

Polypeptides formed by abiotic synthesis

Question 29

Liposomes

Answer 29

Lipids forming a layer over a microsphere

Question 30

Microspheres

Answer 30

Droplets spontaneously formed by proteinoids in water

Question 31

Coacervate

Answer 31

Includes polypeptides, nucleic acids, and polysacchardies

Question 32

Protobionts

Answer 32

The name of the group that encompasses microspheres, liposomes, and coacervates