4.) Animal Reproduction

UIUC ANSC 100 course, 2025

What are species that can only conceive during certain times of the year called?

seasonally polyestrus

What is the master gene for sex determination in mammals?

SRY, located on the Y chromosome

What is a characteristic that allows for sperm that produces both male and female offspring to be separated from each other?

a difference in DNA content

What produces estradiol?

the ovary

What are two hormones the developing embryo produces across species that alerts the mother to the pregnancy?

interferon tau and hCG

Why do producers use artificial insemination in the livestock industry?

to use semen with superior genetics

What triggers the pre-ovulatory LH surge in reflex (induced) ovulators?

Mating

What is one advantage of sexual reproduction?

the offspring are most genetically diverse

What happens with asexual reproduction?

the offspring are clones of the parent

What does the ovary produce?

progesterone and estradiol

What produces a substance that blocks the destruction of the corpus luteum?

The developing embryo

Where is the hypothalamus located?

the brain

What is an example of a reflex (induced) ovulator?

a cat

What is one example of an endocrine disruptor?

bis phenol A (BPA)

What kind of ovulators have a pre-ovulatory LH surge induced by estradiol?

spontaneous

What is required to clone an adult animal?

a cell from the animal to be cloned and an oocyte with the nucleus removed.

What can an endocrine disruptor do?

mimic the effects of hormones, disrupt normal hormone signaling, and cause tumors or birth defects

Administering an additional amount of what hormone would lead to an increase in (hyper-stimulation) of follicular growth and increase ovulation rate?

FSH

What is the function of FSH?

to encourage follicles to develop

What happens in hermaphroditic reproduction?

organisms have both male and female reproductive organs

What is a vesicle released by the sperm to penetrate the zona pellucid of an oocyte?

an acrosome

What is the difference between Y bearing sperm and X bearing sperm?

Y bearing has less DNA

What is FSH produced by?

the anterior pituitary gland

A major change in what factor controls reproduction in seasonally polyestrus animals?

hours of sunlight each day

What is true about the reproduction of the 9-banded armadillo?

Each embryo divides into 4 identical offspring

What reproductive cycle do humans and some primates experience?

menstrual

What kind of animals have embryos that are nourished by egg yolk?

oviparous animals

What is not correct about mammals cervix's?

it is located between the oviduct and the uterus

What produces LH?

the anterior pituitary gland

In pigs, what is located between the vulva and cervix?

vagina

What is true about the corpus luteum (CL)?

The CL is filled with cells

In what kind of ovulators is the pre-ovulatory LH surge induced by estradiol?

spontaneous

In spontaneous ovulators, what induces the pre-ovulatory LH surge?

estradiol

What happens when embryos develop outside of the mother's body?

they use nutrients in the yolk for development

What produces the hormone progesterone?

the corpus luteum

What triggers lysis(destruction) of the corpus luteum in a non-pregnant animal?

prostaglandin F2-alpha

What is one explanation for a person who appears to be female yet has both an X and Y chromosome?

the person has a mutation on their Y chromosome

What is not a function of the epididymis?

sperm production

What is the function of GnRH?

control LH and FSH release

What do ovarian follicles release during ovulation?

oocytes

In what type of animals to eggs remain inside of the mother until they're hatched?

ovoviviparous

What is hCG produced by?

the developing embryo

What is an example of an endocrine disruptor?

bis phenol a (BPA)

What type of animals have embryos nourished by a placenta?

viviparous

What does the hypothalamus produce?

GnRH

What does the luteinizing hormone (LH) NOT control?

prevention of the release of the oocyte from the follicle