The Reproductive System, Development, and Inheritance

Vocabulary flashcards covering the male and female reproductive systems, stages of development from fertilization to birth, and principles of inheritance.

Gamete

A specialized sex cell that has $23$ chromosomes.

Testes

The male gonads located in the scrotum that produce sperm.

Dartos and cremaster muscles

Muscles that contract to pull the testes closer to the body for warmth in cold conditions or relax to keep them cool in heat.

Tunica albuginea

A covering of the testes that separates them into $300-400$ lobules; it also covers the ovaries.

Seminiferous tubules

Tightly coiled tubules within each testis where sperm development occurs.

Sertoli cells

Cells in the seminiferous tubules that control sperm production, germ cell survival, and create the blood-testes barrier.

Blood-testes barrier

A barrier created by Sertoli cells to keep blood borne substances and autoimmune responses away from developing germ cells.

Spermatogenesis

The process of sperm development which begins at puberty and takes about $64$ days for one cycle.

Spermatogonia

The least mature germ cells that divide by mitosis and contain all $46$ chromosomes.

Cryptorchidism

The term for when one or both testes fail to descend into the scrotum prior to birth.

Epididymis

A structure where newly formed sperm continue to mature for about $12$ days and are collected for ejaculation.

Ductus deferens (vas deferens)

A muscular tube that carries sperm from the epididymis to the spermatic cord during ejaculation.

Seminal vesicles

Glands that produce $60\%$ of semen fluid, which is high in fructose to provide energy for sperm.

Prostate

A gland that adds fluid to the semen to help it coagulate.

Bulbourethral glands

Glands that release pre-ejaculate fluid to lubricate the urethra and clean away urine residue.

Corpora cavernosa

Two of the three sections of erectile tissue found in the penile shaft.

Corpus spongiosum

One of the three sections of erectile tissue in the penile shaft that surrounds the urethra.

Vasocongestion

The process of more blood entering the penis than leaving, leading to an erection.

Ovaries

The female gonads that produce oocytes.

Vulva

The name for the external female reproductive area.

Hymen

A partial membrane covering the vaginal canal that always allows fluid to flow out.

Follicle

An oocyte surrounded by supporting cells in the ovarian cortex.

Oogenesis

The process of oocyte production.

Folliculogenesis

The process of growth and development of ovarian follicles.

Atresia

The death of ovarian follicles, which occurs in $99\%$ of follicles.

Corpus luteum

A structure formed from a collapsed follicle after ovulation that produces progesterone to inhibit GnRH.

Uterine tubes (fallopian tubes)

Tubes with cilia that create a current to move the oocyte from the ovary to the uterus.

Pelvic inflammatory disease

A condition caused by contagions moving into the uterine tubes, potentially leading to scarring and infertility.

Menses phase

The phase of the menstrual cycle when the thicker functional layer of the endometrium is shed.

Proliferative phase

The phase where the endometrium regenerates, ending at ovulation.

Secretory phase

The phase high in progesterone and glucose-rich fluid to prepare for zygote implantation.

Bipotential

The ability of many embryonic cells to develop into either male or female reproductive structures.

Capacitation

A process sperm must undergo inside the female to allow its enzymes to penetrate the oocyte.

Fast block

The depolarization of the oocyte plasma membrane after a sperm joins to prevent other sperm from entering.

Slow block

The process where sperm receptors are destroyed and the outer cover is coated with protein to become impenetrable.

Zygote

The first single-celled diploid cell of an offspring formed by the joining of a haploid ovum and sperm.

Gestation

The period of development for the offspring, lasting approximately $38-40$ weeks ($270$ days).

Conceptus

The developing offspring as it travels toward the uterus during the pre-embryonic stage.

Blastocoel

The inner mass of cells in a conceptus that are totipotent and will become the embryo.

Trophoblasts

The outer ring of cells in a conceptus that will develop into the placenta.

Human chorionic gonadotropin (HCG)

A hormone produced during implantation that allows the corpus luteum to survive and produce hormones to stop menses.

Placenta previa

A complication where the placenta covers the opening to the cervix.

Ectopic pregnancy

A condition where implantation occurs outside of the uterus.

Embryonic folding

The process during development where membranes wrap to form a 3-dimensional structure.

Organogenesis

The process of developing all organs, which is underway by week $8$ of the embryonic period.

Relaxin

A hormone secreted to loosen hip ligaments and help dilate the cervix.

Involution

The term for the uterus returning to its original size after childbirth.

Brown fat

Vascular fat full of ATP that an infant breaks down for warmth since they cannot shiver efficiently.

APGAR score

A scoring system used to judge physical health in the first few minutes after birth.

Colostrum

A fluid high in immunoglobulin produced by the mammary glands for the first $3$ days postpartum.

Genotype

A person's underlying genetic makeup.

Phenotype

A person's outward appearance and behavior based on their genes.

Allele

A copy of a gene; individuals have two for each trait, which can be homozygous or heterozygous.

Down's syndrome

A genetic disorder resulting from having $3$ copies of chromosome $21$.

Turner syndrome

A genetic disorder characterized by having only one X chromosome, resulting in sterile female reproductive organs.