Dyads are visible in

both mitosis and meiosis

tetrads are visible in

meiosis only

product is 2 diploid daughter cells genetically identical to the mother cell

mitosis only

product is 4 haploid daughter cells quantitatively different from the mother cell

meiosis only

involves the phases prophase, metaphase, anaphase and telophase

both mitosis and meiosis

occurs throughout the body

mitosis only

occurs only in the ovaries and testes

meiosis only

provides cells for growth and repair

mitosis only

hologoues synapse: chiasmata are seen

meiosis only

chromosomes are replicated before the division process begins

both mitosis and meiosis

Provides cells for replication of the species

meiosis only

consists of 2 consecutive nuclear divisions, without chromosomal replication occurring before the second division.

meiosis only

Describe the process of synapsis

The pairing of homologous chromosomes (23 tetrads become attached to spindle fibers & begin to align on the equator.

How does crossover introduce variability in the daughter cells?

The homologues seperate from one another, breaking & exchanging parts- where crossovers occur

Define homologous chromosomes

Egg & sperm chromosomes that carry genes for the same traits (1 paternal, 1 maternal)

primative stem

spermatogonium

haploid

secondary spermatocyte, spermatid, sperm

Provides nutrients to developing sperm

sustentacular cells

products of meiosis II

spermatid

product of spermiogenesis

sperm

product of meiosis I

spermatocyte

Why are spermatids not considered functional gametes?

They are non-motile and have too much excess baggage to function well in a reproductive capacity.

Differentiate between spermatogenesis and spermiogenesis

Spermiogenesis is the final stage of spermatogenesis, which sees the maturatin of spermatids into mature, mobile spermatozoa. * formation of haploid gametes by Male sloughing off excess spermatid cytoplams to form a motle functioning sperm

Draw a sperm, label: acrosome, head, midpiece and tail. Beside each label, note the composition, and function of each sperm structures.

acrosome:(composition & function) penetrating device containing digestive enzymes

head:(composition & function) genetic region, nucleus

midpiece:(composition & function) contains mitochondria which provide ATP

tail:(composition & function) contactile filaments (locomotor region)

The lifespan of a sperm is very short? What anatomical characterists might lead you to suspect this even if you don't know it's life span?

No cytoplasm in which to store nutrients.

The sequence of events leading to germ cell formation in the female begins during fetal development, by the time the child is born, all viable oogonia have been converted to

primary oocytes

How does the total germ cell potential of the female compare to that of the male?

much smaller, and the total number is predetermined

Female gametes develop n structures called follicles. What is a follicle?

A saclike structure containing follicle cells in one or more layers that enclose a developing gamete.

How are primary and vesicular follicles anatomically different?

Primary follice=primary oocyte; a single layer of cuboidal/columnar follicle cellsSecondary follice=several layers of cuboidal/columnar cells collectively called the membranous granulosa which secrete follicular fluid

What is a corpus luteum?

It is what's left of the follicle after a woman ovulates. Glandular ovarian structure that produces progesterone. The ruptured vescicular follicle is converted to corpus leuteum.

What is the major hormone produced by the vesicular follicle?

Estrogen

What is the major hormone produced by the corpus luteum?

Progesterone (and some estrogen)

The cell type you would find forming part of the primary follicle in the ovary

primary oocyte

The cell type you would find in the uterine tube before fertilization

secndary oocyte

The cell type you would find in the mature vesicular follicle of the ovary

secondary oocyte

The cell type you would find in teh uterine tube shortly afer sperm penetration

ovum

The cellular product of spermatogenesis is four _____________; the final product of oogenesis is one ________ and three ____________

spermatids, ovum, polar bodies.

What is the function of the unequal result of oogenesis in the female?

to provide the ovum or functional gamete w/adequate nutritional reserves so that it can survive it;s journey to the uterus.

What is the fate of the 3 tiny cells producted during oogenesis? Why?

They will deteriorate; they lack sustaining cytoplasm w/nutrient reserves.

The hormone produced by primary follicles in the ovaries

FSH

Ovulation occurs after it's burstlike release

LH

Exert negative feedback on the anterior pituitary relative to FSH secretion

Estrogen and progesterone

Stimulates LH release by the anterior pituitary

Estrogen

Stimulates the corpus leuteum to produce progesterone and estrogen

LH

Maintains the hormonal production of the corpus luteum in a non pregnant woman

LH

Why does the corpus luteum deteriorate toward the end of the ovarian cycle?

Because blood levels of the anterior pituitary hormone LH are very low

The amount of LH in the blood during meses is greater than or less than the amount of LH in the blood at ovulation?

less than

The amount of FSH iin the blood on day 6 of the cycle is greater than or less than the amount of FSH in the blood on day 20 of the cycle

greater than

The amount of estrogen in the blood during menses is greater or lesser than the amount of estrogen in the blood at ovulation?

less than

The amount of progesterone in the blood on day 14 is less than or greater than the amount of progesterone in the blood on day 23?

less than

The amount of estrogen in the blood on day 10 is greater than or less than the amount of progesterone in the blood on day 10?

greater than

What uterine tissue undergoes dramatic changes during the menstrual cycle?

endometrium

When during the female menstruaol cycle would fertilization be unlikely? Explain why?

Anytime but the three-day interval (days 14-16) around ovulation (28 day cycle assumed)

Assume that a woman could be an "on demand" ovulator like the rabbit, in which copulation stimulates the hypothalamic-anterior pituitary axis and causes LH release, and an oocyte was ovulated and fertilized on day 26 of her 28-day cycle. Why would a successful pregnancy be unlikely at this time?

The uterine lining goes through a cycle of building up every cycle to accept an embryo. By the time day 26 comes along, the lining is getting ready to slough off during the next period. Most likely the lining of the uterus would not be able to support the implantation and development of the embryo at this time.