Reproduction and development Part 2 Flashcards
Many(but not all) animals have gonads.
What are gonads?
Organs that produce gamete
More elaborate systems include sets of
accessory tubes and glands that carry, nourish, and protect gametes and sometimes developing embryos.
Let’s talk about Insects
- Most insects have separate sexes with complex reproductive systems
-In many insects, the female has a spermatheca
-This way fertilization can occur under conditions likely to be well-suited to the survival of offspring.
Spermathaca
Female insects have these. It can store sperm and keep it alive for extended periods of time
Cloaca
a common opening between the external environment and the digestive, excretory, and reproductive systems.
-common in nonmammalian vertebrates
-mammals usually have a separate opening to the digestive tract
Male’s external reproductive organs are called the
scrotum and penis
The internal reproductive organ of the male is the___ and it produces
-gonads
-produces sperm and reproductive hormones, accessory glands that secrete products essential to sperm movement, and ducts that carry sperm and glandular secretions
The male gonads or TESTES
produce sperm in highly coiled tubes called seminiferous tubules (A testis within the scrotum is a testicle)
seminiferous tubules
highly coiled tubes. (A testis within the scrotum is a testicle)
Production of normal sperm cannot occur at the body temperatures of most mammals
True or False
True
Scrotum
- A fold of the body wall
- maintains testis temperature at about 2 degrees celsius below the core body temperature
Epididymis
From the seminiferous tubules of the testis, sperm passes into the coiled duct
During ejaculation
sperms are propelled through the Muscular Vas Deferens and the Ejaculatory Duct. Then exit the penis through the Urethra.
Muscular V D—>Ejaculatory D—> Urethra
Semen is composed of
sperm and secretions from three sets of accessory glands
Two seminal vesicles contribute
about 60% of the total volume of semen
