Chapter 9: reproductive strategies

Question 1

sexual reproduction

Answer 1

reproduction mechanism in which progeny inherit DNA from 2 parents
- gametes (haploid germ cells) produce through meiosis
- 2 gametes combine = mixing of chromosomes –> fertilization –> diploid zygote

Question 2

Asexual reproduction

Answer 2

reproductive mechanism in which progeny inherit DNA from 1 parent through vegetative reproduction or parthenogenesis

Question 3

Vegetative reproduction

Answer 3

when an individual is produced from the nonsexual tissues of the parent
- Ex: plants growing new shoots

Question 4

Clones

Answer 4

individual produced through asexual reproduction has same genotype as parent

Question 5

Binary fission

Answer 5

reproduction though duplication of genes followed by division of cell into 2 identical cells; splitting in half
- ex: starfish

Question 6

Haploid Parthenogenesis (“virgin birth”)

Answer 6

form of asexual reproduction in which an embryo is produced w/o fertilization
- Diploid egg, doesn’t need sperm
- Produce clones or w/ variation
- can ONLY produce females

Question 7

Cost of sexual reproduction

Answer 7

energy and resources/cost for sexual organs
- Reduces fitness, increases risk of predation and parasitism

Question 8

Cost of meiosis

Answer 8

~50% reduction in # of parent’s genes passed onto next generation via sexual reproduction versus asexual reproduction

Question 9

cost of meiosis can be counterbalanced by ___ in hermaphrodites

Answer 9

can contributed twice as many copies of genes to offspring

Question 10

cost of meiosis can be counterbalanced by ___

Answer 10

a male helping a female take care of offspring

Question 11

Purging mutations

Answer 11

in sexual reproduction, deleterious mutations may not be transmitted to gametes
- Gametes produced do not form zygote w/ mutation

Question 12

Red queen hypothesis

Answer 12

hypothesis that sexual selection allows hosts to evolve at rate that can counter the rapid evolution of parasites

Question 13

benefits of sexual reproduction

Answer 13

purging mutations, genetic variation, environmental variation, evolving to be able to withstand new parasites and pathogens

Question 14

Perfect flowers

Answer 14

flowers w/ male and female parts

Question 15

Simultaneous hermaphrodites

Answer 15

individuals w/ male and female reprodictve funtions at the same time (self-fertilization)

Question 16

Sequential hermaphrodites

Answer 16

individuals w/ either male or female reproductive function and then switch to other (out-crossing)

Question 17

Monoecious

Answer 17

plants w/ separate male and female flowers on same individual

Question 18

Dioecious

Answer 18

plants w/ either only male flowers or only female flowers on 1 individual

Question 19

Genetic sex determination

Answer 19

sex-specific chromosomes determine sex

Question 20

Genetic sex determination in mammals

Answer 20

XX = female
XY = male

Question 21

Genetic sex determination in birds

Answer 21

ZW = female
ZZ = male
- allows for male and females to be produced through parthenogenesis

Question 22

Environmental sex determination

Answer 22

process in which sex is determined by environment

Question 23

Temperature-dependent sex determination

Answer 23

sex determined by temperature at which eggs develop
- sex determination = phenotypic plasticity

Question 24

temperature-dependent sex determination in turtles

Answer 24

• lower temps = males
• higher temps = females

Question 25

___ determine ratio of male/females produced

Answer 25

- females determine who receives X or Y - selective abortion

Question 26

Local mate competition

Answer 26

competition for mates occurs in very limited area; only a few males are required to fertilize all the females

Question 27

Mating system

Answer 27

of mates each individual has and the permanence of the relationship w/ those mate

Question 28

4 mating systems

Answer 28

promiscuity, polyandry, polygyny, monogamy

Question 29

Promiscuity

Answer 29

mating system in which males mates w/ multiple females and females mate w/ multiple males; do not create lasting social bond

Question 30

Polygamy

Answer 30

mating system in which 1 individual of 1 sex forms long-term social bonds w/ 2+ individuals of opposite sex

Question 31

Polygyny

Answer 31

mating system in which male mates w/ more 2+ females

Question 32

Polyandry

Answer 32

mating system in which female mates w/ 2+ males

Question 33

Monogamy

Answer 33

mating system w/ social bond b/w 1 male and 1 female persists through bearing offspring

Question 34

Extra-pair copulations

Answer 34

individual that has social bond w/ mate but also breeds w/ others

Question 35

Mate guarding

Answer 35

behavior in which 1 partner prevents other partner from participating in extra-pair copulations

Question 36

Sexual selection

Answer 36

natural selection for sex-specific traits related to reproduction

Question 37

Sexual dimorphism

Answer 37

difference in phenotype b/w males and females of same species

Question 38

Primary sexual characteristics

Answer 38

traits related to fertilization

Question 39

Secondary sexual characteristics

Answer 39

traits related to differences b/w the sexes in terms of body size, ornaments, color, and courtship

Question 40

2 types of female preference

Answer 40

material benefits and nonmaterial benefits

Question 41

Material benefits

Answer 41

physical items males can provide females - Ex: site for raising offspring, high-quality territory, and abundant food

Question 42

Nonmaterial benefits

Answer 42

female preference for specific appearance on males based on the good genes and good healthy hypotheses

Question 43

Good healthy hypothesis

Answer 43

individual chooses healthiest mates

Question 44

Good genes hypothesis

Answer 44

individual chooses a mate that possesses superior genotype

Question 45

Runaway sexual selection

Answer 45

selection for preference of sexual trait and selection for that trait continue to reinforce each other

Question 46

Handicap principle

Answer 46

greater the handicap an individual carries, greater its ability to offset that handicap

Question 47

Budding

Answer 47

little buds that pop off the mom plant when ig enough

Question 48

Vegetative

Answer 48

reproduce through bulbs or tubers

Question 49

Fragmentation

Answer 49

parents breaks into pieces and pieces develop as offspring (Starfish)

Question 50

benefits to sexual reproduction

Answer 50

- gene variation (more combinations of genes = more variation = less susceptible to disease = more likely to survive

Question 51

protogyny

Answer 51

changing sex female --> male