Sex Determination and Differentiation

Question 1

someone whose gender identity does not match their biological sex

Answer 1

transgender

Question 2

what is sexual orientation

Answer 2

defines the sex and or gender preferred by an individual as a romantic or sexual partner

Question 3

prefers the opposite sex or gender

Answer 3

heterosexual

Question 4

prefers the same sex and or gender

Answer 4

homosexual

Question 5

prefers members of both sexes and or gender

Answer 5

bisexual

Question 6

generation of new individuals from existing ones, fundamental characteristics of life

Answer 6

reproduction

Question 7

creation of offspring from single individual; results in genetic clones

Answer 7

asexual reproduction

Question 8

creation of offspring through fertilization of gametes, results in genetic combination of parents

Answer 8

sexual reproduction

Question 9

what are two-fold cost of sex

Answer 9

• cost of meiosis/ fertilizatin
• cost of males

Question 10

what are other costs of sex

Answer 10

mate searching
mating
sexually-transmitted diseases
genetic recombination

Question 11

what are benefits of sex

Answer 11

increased genetic variation

Question 12

why does sex exist

Answer 12

it allows for adaptation to changing environment

Question 13

what are negative of mate searching

Answer 13

it takes time, energy and predation

Question 14

why can be mating negative

Answer 14

can cause injury and death

Question 15

what is negative about sexually transmitted diseases

Answer 15

there can be parasites and pathogens

Question 16

what is negative about genetic recombination

Answer 16

there can be a loss of beneficial alleles

Question 17

what dominates multicellular forms of life

Answer 17

sexual production

Question 18

capable of producing both ‘male’ and ‘female’ gametes

Answer 18

hermaphrodites

Question 19

example of hermaphrodites

Answer 19

sea slugs or hamlet fish

Question 20

what can act on gamete production

Answer 20

selection

Question 21

what is asymmetrical gamete investment

Answer 21

anisogamy

Question 22

when you have selection on gametes, there are two strategies which are

Answer 22

1. maximize fertilization rate
2. maximize development, growth, and survival

Question 23

anisogamy for females means

Answer 23

fewer and larger gametes (eggs)

Question 24

what is the difference between the sexes in secondary sexual characteristics

Answer 24

sexual dimorphism

Question 24

anisogamy for males means

Answer 24

many, small, motile gametes (sperm)

Question 25

natural selection for mating success

Answer 25

sexual selection

Question 26

competition among individuals of one sex for mates of the opposite sex

Answer 26

intrasexual selection

Question 27

occurs when individuals of one sex are choosy in selecting their mates

Answer 27

intersexual selection

Question 28

the process of becoming male or female

Answer 28

sexual differentiation

Question 29

primary step in sexual differentiation; often occurs at fertilizatioin

Answer 29

sex determination

Question 30

ovaries produce what

Answer 30

eggs

Question 31

testes produe

Answer 31

sperm

Question 32

what contains tissue that can become ovaries or testes

Answer 32

embryo

Question 33

epididymis, vas deferens, seminal vesicles, etc

Answer 33

wolffian duct

Question 34

fallopian tubes, uterus, cervis

Answer 34

mullerian duct

Question 35

gene that codes for TDF

Answer 35

SRY (sex determining region of the Y chromosome)

Question 36

protein that regulates gene expression for testes development

Answer 36

testis determination factor (TDF)

Question 37

what connects gonads to external environment

Answer 37

accessory sex organs

Question 38

what is required for wolffian duct development in males

Answer 38

testosterone

Question 39

what is secreted by testes; required for regression of mullerian ducts in males

Answer 39

mullerian inhibitory hormone

Question 40

penis and scrotum in males; clitoris and vaginal labia in females

Answer 40

external genitalia

Question 41

needed for development of male genitals

Answer 41

5a-dihydrotestosterone (DHT)

Question 42

enzyme that converts T to DHT

Answer 42

5a-reductase

Question 43

what is the default sex

Answer 43

female

Question 44

XO; develop normally as females, but must be treated with sex steroids as teenagers to induce puberty

Answer 44

turner syndrome

Question 45

females exposed to androgens secreted from ovaries or adrenal glands during development; results in slight to moderate masculinzation

Answer 45

congenital adrenal hyperplasia

Question 46

XY; complete or partial absence of androgen receptors

Answer 46

androgen insensitivity syndrome or testicular feminized mutant

Question 47

XY; individuals lack the enzyme needed to reduce T to DHT

Answer 47

5a- reducatase deficiency

Question 48

extra X or Y chromosome

Answer 48

sex chromosome trisomy

Question 49

XXY; develop as males, often have learning disabilities and are usually sterile

Answer 49

klinefelter

Question 50

males are generally taller than average, lower intelligence; used to think represented at higher than average frequencies in prison populations- currently disputed

Answer 50

XYY syndrome

Question 51

differences in appearance, physiology and behavior between types of males

Answer 51

alternative male morphs

Question 52

what posses ovotestes and produce both sperm and egg

Answer 52

simultaneous hermaphrodites

Question 53

what begin life as female and switch to male or begin as male and switch to female

Answer 53

sequential hermphrodites

Question 54

term for beginning life as a female

Answer 54

protogynous

Question 55

term for beginning life as a male

Answer 55

protoandrous

Question 56

if your bigger in fish what does it mean

Answer 56

it can produce more eggs

Question 57

being bigger in clownfish it means

Answer 57

you can produce more eggs

Question 58

what is the basis for behavior

Answer 58

the brain

Question 59

what states that hormones secreted early in development organize the brain for later hormonal activation as adults

Answer 59

organizatinal/ activational hypothesis

Question 60

who states the organizational/ activationalhypothesis

Answer 60

william c young

Question 61

mating posture assumed in females

Answer 61

lordosis

Question 62

mating posture assumed by males

Answer 62

mounting

Question 63

what is mating behavior regulated by

Answer 63

gonadal hormones as adults

Question 64

OVX means

Answer 64

ovaries removed

Question 65

effects of hormones during a critical period of development to determine how the animal responds to hormones in adulthood

Answer 65

organizational effects

Question 66

acute effects of hormones on behavior during adulthood

Answer 66

activational effects

Question 67

the time period during which organizational hormones can have their effects

Answer 67

critical period

Question 68

what is thought to have masculinizing effects in many species, if it reaches the brain

Answer 68

estradiol

Question 69

what is the aromatization hypothesis

Answer 69

testosterone has its effects by being aromatized to E2

Question 70

in developing female rodents what is present and binds to E2 and what does it do

Answer 70

alpha-fetoprotein and it prevents E2 from acting on its recepotors and causing masculinzation

Question 71

what are some factors influencing sex differentiation

Answer 71

- in birds, maternal provisoning of steroids too offspring through egg yolk - in mammals, placement of developing fetuses in the uterine environment - paternal care by mothers - levels of stress - endocrine-disrupting chemicals

Question 72

what are compounds found in the environment that mimic steroid hormone function

Answer 72

endocrine-disrupting chemicals