AP Biology Ch 46 & 47

Zygote

A fertilized egg is called:

At low levels, it inhibits gonadotropins (FSH & LH), at high levels, it increases the levels of gonadotropins by stimulating the hypothalamus to produce more GnRH

How does the amount of estrogen effect ovulation?

1. During meiosis in females, only one of the four resulting cells becomes a mature egg cell. In males, all four cells will produce mature sperm. 2. Females have a large number of their egg cells at birth. They finish maturation with each ovulation. Males do not start producing sperm until puberty. 3. Females undergo menopause around age 50. Males continue producing sperm throughout their lives.

How is the production of eggs in females different than the production of sperm in males?

Gonads

The organs that produce gametes are called:

Haploid sex cells

What are gametes?

Chemical signals that influence the behavior or physiology of another animal.

What are pheromones?

It does not require a watery environment and is more efficient than external fertilization. For this reason, less energy is spent on producing large quantities of sperm and eggs.

What are the advantages of internal fertilization?

Female: Egg, Male: Sperm

What are the male and female gametes?

Females: Ovaries Males: Testes

What are the male and female gonads in mammals?

Leydig cells

What cells on the male testes are responsible for secreting testosterone?

Ectoderm

What embryonic germ layer produces the skin, epithelium of mouth, and tooth enamel?

Endoderm

What germ layer produces mainly the epithelial tissue of the body?

Mesoderm

What germ layer produces the muscular and skeletal system?

Follicle stimulating hormone and Lutienizing hormone.

What two hormones secreted by the anterior pituitary stimulate follicle growth and ovulation?

First trimester

During which trimester does most of the organ development take place?

Second trimester

During which trimester does the corpus luteum deteriorate and the placenta takes over the production of progesterone?

Fission produces two individuals of roughly equal size whereas budding produces a new individual as an outgrowth of an adult individual.

Explain how budding and fission are different forms of asexual reproduction.

Organisms that produce a large number of offspring tend to invest more energy in producing offspring and less in parental care. Organisms that invest less energy in producing offspring tend to invest more in parental care.

Explain the inverse relationship between number of young and parental care.

An egg is produced but, it is not fertilized and is genetically identical to the parent.

Explain why parthenogeny is considered to be a form of asexual reproduction.

The reproductive tracts and digestive tracts are have seperate openings.

Hows is the mammalian reproductive system different than the reproductive system of other vertebrates?

When the egg is fertilized.

In humans, when does conception occur?

Blastula

The first 7 divisions of a zygote produce a

Gastrulation

The process by which the blastula folds in upon itself, forming a body cavity

Ectoderm, mesoderm, endoderm

The three layers that are produced by gastrulation are

Luteinizing hormone

What hormone from the anterior pituitary stimulates the production of testorsterone from Leydig cells?

Progesterone and estrogen.

What hormones are produced by the corpus luteum that inhibit the production of gonadotropins and promote thickening of the endometrium?

A sac found in female insects where sperm can be stored and later used to fertilize eggs.

What is a spermatheca?

External fertilization is when eggs are released by a female into the environment and later fertilized with a male's sperm. Internal fertilization is when sperm are deposited in or near a female's reproductive tract and fertilization takes place within the reproductive tract.

What is the difference between internal and external fertilization?

The thickening of the endometrium followed by the disitegration and shedding of the endometrium through menstration.

What occurs during a menstral cycle?

The development and release of the egg cell, followed by the formation and degeneration of the corpus luteum.

What occurs during ovarian cycle?

FSH

What other hormone of the anterior pituitary stimulates spermatogenesis?

From the corpus luteum glands that form on the surface of the ovary.

Where are estrogen and progesterone produced?