ANSC 201 repro pt 1

testicle

Descend through inguinal canal to scrotum around time of birth

seminiferous tubules

Spermatogenesis occurs

Interstitial tissue

lydeig cells

scrotum

house and protect testicles

1. Describe the two types of cryptorchidism.

Unilateral cryptorchidism:
One testis fails to descend into the scrotum, while the other descends normally.

Bilateral cryptorchidism:
Both testes fail to descend into the scrotum.

epididymis function

store sperm

provision of maturation space for sperm cells

nutrition of sperm cells through secreted substances

Vas deferens

carries sperm cells and substances from eipdidymis to urethra

ampulla at the end

1. Name two accessory sex glands and a function they might serve.

Bulbo Urethral Gland ( Cowpers)- Secretes a mucus-like fluid that lubricates the urethra and neutralizes acidic urine residue prior to ejaculation.

Prostate Gland- Produces a fluid that nourishes and protects sperm and contributes to semen volume and motility.

variations in semen in chicken

more concentrated in avian

oogenesis

production of eggs

estrogen

from growing follicles, produces most of the female characteristics

progesterone

from CL, formed ater ovulation when follicle collapses, helps maintain pregnancy

Relaxin

loosens pelvic area during parturation

Describe the process of sperm transport starting from the vagina and ending at the oviduct.

vagina to uterus: sperm travels by its own motility using its tail

uterus to oviduct: sperm uses its own motility plus muscle contractions of the female

cervix

lower outlet of uterus made of CT

changes with stages of estrous and pregnancy

open when animal in heat and closed when pregnant to prevent invasion of bacteria

Magnum

secretes most of albumen layers

mitosis

Asexual division of body cells

number of chromosomes stays constant

meiosis

sexual reproduction

occurs in seminiferous tububles or ovary

resulting cells are haploid, ½ the diploid #

Contrast spermatogenesis in males with oogenesis in females. Be sure to include the number of functional cells at the end of the process and whether each is continuous or cyclic.

Spermatogenesis:
Produces 4 functional sperm cells from each primary spermatocyte and is a continuous process after puberty.

Oogenesis:
Produces 1 functional ovum (plus polar bodies) from each primary oocyte and is a cyclic process that follows the estrous/menstrual cycle.

Portion of the avian oviduct that secretes most of the albumen  layers.  

Magnum

Volatile chemical products that can trigger mating responses in 

  receptive males.

Pheromone

The type of placenta found in ruminants.

Cotyledonary

 An extraembryonic membrane that provides early nutrients to the  developing embryo and degenerates after a few days. 

Yolk sac

semen deposition in swine and horses

cervix

semen deposition in most animals, cattle, sheep, goat

uterus

semen deposition in bird

cloaca

Why is conservation of cytoplasm important during gametogenesis?

Ensures the mature egg retains the vast majority of cytoplasm, nutrients, organelles, and maternal mRNA required for early embryonic development, cellular metabolism, and rapid cell divisions following fertilization

how long can sperm be stored in the vagina in bird

up to 7 days

sperm have long or short life span in animals

short