Biology slides 7
What is the primary purpose of the male reproductive system?
To support the production, storage, and release of sperm cells.
What functions does the female reproductive system support?
Development of an egg, its fertilization, development and birth of a fetus, and nourishment to the newborn.
What are gametes?
Sperm and egg cells that contain half of the parent's DNA.
What is formed when sperm and egg cells combine?
A zygote.
What determines an individuals chromosomal sex?
The combination of sex chromosomes at the moment of zygote formation.
What is gonadal sex?
The determination of whether gonads become ovaries or testes, influenced by genes on sex chromosomes.
What is phenotypical sex?
The physiological characteristics influenced by hormones produced from the gonads.
What is the process of gametogenesis?
The formation of gametes, which occurs differently in males and females.
How many distinct gametes are produced during spermatogenesis?
Four distinct sperm cells.
How many gametes are produced during oogenesis?
One ovum (egg) is produced, while other cells become polar bodies and are not used for fertilization.
When does spermatogenesis begin and how long does it continue?
It begins at puberty and continues indefinitely.
When does oogenesis begin and how is it regulatd?
It begins during fetal development but pauses until puberty, resuming monthly during the menstrual cycle.
What are the roles of Leydig and Sertoli cells in spermatogenesis?
Leydig cells produce testosterone, while Sertoli cells support growing spermatocytes and help accumulate testosterone.
What is the function of the seminal vesicle in male reproduction?
It produces 60% of the fluid in semen, containing fructose to fuel sperm and protect them from the vaginal environment.
What does the prostate gland contribute to semen?
It produces a fluid that helps sperm survive in the vagina and makes semen less thick.
What is the function of the bulbourethral gland?
It produces a clear fluid prior to ejaculation to neutralize any urine in the urethra.
What hormones are involved in the regulation of spermatogenesis?
GnRH from the hypothalamus stimulates the pituitary to produce FSH and LH, which act on the testes.
What is the role of the corpus luteum in the female reproductive cycle?
It signals the uterus to prepare for a fertilized egg and releases hormones to support the endometrium.
What happens to the corpus luteum if a fertilized egg arrives in the uterus?
It continues to produce hormones to maintain the uterine lining.
What are fraternal twins?
Twins resulting from the fertilization of multiple eggs.
What are monozygotic twins?
Twins resulting from the spontaneous division of a single zygote.
What triggers milk production in mammary glands during pregnancy?
Prolactin (PRL) released by the pituitary gland, stimulated by the hypothalamus.
What inhibits the action of prolactin during pregnancy?
High levels of progesterone prevent prolactin from working effectively until near the end of pregnancy.
What is the ovarion cycle composed of?
Two phases: follicular and luteal phases.
What occurs during ovulation?
The dominant follicle releases the ovum from the ovary.
What is the significance of the endometrium during the menstrual cycle?
It thickens to prepare for a fertilized egg and is shed if fertilization does not occur.
What hormonal changes occur during the follicular phase of the ovarian cycle?
FSH stimulates follicle development, and the dominant follicle produces estrogen, which promotes endometrium growth.