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What is the function of the male reproductive system?

To produce sperm (gametes) and male sex hormones.

What are gametes?

Sex cells (sperm and egg) that are haploid.

What are somatic cells?

Body cells that are diploid.

What is spermatogenesis?

The production of sperm through meiosis.

What is meiosis?

Two rounds of cell division that convert a diploid cell into haploid cells.

What is a diploid cell?

A cell with two copies of each chromosome.

What is a haploid cell?

A cell with one copy of each chromosome.

How does meiosis differ from mitosis?

Meiosis has two divisions and produces four genetically different haploid cells; mitosis has one division and produces two identical diploid cells.

Where does mitosis occur?

Throughout the body.

Where does meiosis occur?

Only in the gonads.

What happens during Meiosis I?

Homologous chromosomes separate and DNA recombination occurs.

What happens during Meiosis II?

Sister chromatids separate.

When does spermatogenesis begin?

At puberty.

Does spermatogenesis stop at any point in life?

No, it continues throughout a man’s lifetime.

Is a spermatogonium haploid or diploid?

Diploid.

Is a primary spermatocyte haploid or diploid?

Diploid.

Is a secondary spermatocyte haploid or diploid?

Haploid.

Are spermatids haploid or diploid?

Haploid.

Are spermatozoa haploid or diploid?

Haploid.

What is spermiogenesis?

Differentiation of spermatids into mature sperm.

What are the three main parts of sperm?

Head, midpiece, tail.

What is the function of the acrosome?

Contains enzymes that help the sperm penetrate the egg.

What is contained in the nucleus of the sperm?

The father’s DNA.

What is the function of the midpiece?

Contains mitochondria to produce ATP.

What does the tail do?

Provides motility for the sperm.

Where is sperm produced?

In the seminiferous tubules of the testes.

What layers cover the testes?

Tunica albuginea (deep) and tunica vaginalis (superficial).

Where does sperm go after seminiferous tubules?

Rete testes.

Where does sperm go after the rete testes?

Efferent ductules.

Where does sperm mature and gain motility?

Epididymis.

What comes after the epididymis?

Vas deferens.

What is contained in the spermatic cord?

Vas deferens, blood vessels, and nerves.

Where does the vas deferens empty?

Ejaculatory duct.

What glands empty into the ejaculatory duct?

Seminal vesicles.

What do seminal vesicles secrete?

Prostaglandins and fructose.

What is the function of prostaglandins?

Stimulate uterine contractions.

What is the function of fructose?

Provides energy for sperm.

What does the prostate gland secrete?

Alkaline fluid.

Why is prostate fluid important?

It neutralizes the acidic vaginal environment.

What do bulbourethral glands secrete?

Pre-ejaculate lubricant.

What is the purpose of pre-ejaculate?

Lubricates and cleanses the urethra.

What are the three parts of the urethra?

Prostatic, membranous, and penile.

Where does semen exit the body?

External urethral meatus.

What structures make up the penis?

Shaft, glans, external urethral meatus.

What is the prepuce?

Foreskin.

What erectile tissues are in the penis?

Two corpora cavernosa and one corpus spongiosum.

Why is the corpus spongiosum important?

It protects the urethra during erection.

What muscles help propel semen?

Bulbospongiosus and ischiocavernosus.

What is the scrotum?

A sac that houses the testes.

What do the testes produce?

Sperm and testosterone.

What muscles regulate testicular temperature?

Cremaster and dartos muscles.

What is cryptorchidism?

Failure of one or both testes to descend.

What is a hydrocele?

Fluid trapped in the tunica vaginalis.

What are alleles?

Different versions of a gene.

What is a dominant allele?

An allele that determines the phenotype.

What is a recessive allele?

An allele masked by a dominant allele.

What does homozygous mean?

Two identical alleles.

What does heterozygous mean?

Two different alleles.

What is genotype?

Genetic makeup.

What is phenotype?

Physical appearance.

What is a monohybrid cross?

A Punnett square involving one trait.

What is the phenotype ratio for a heterozygous monohybrid cross?

3:1.

What is the genotype ratio for a heterozygous monohybrid cross?

1:2:1.

What is a dihybrid cross?

A Punnett square involving two traits.

What is the Law of Segregation?

Alleles separate during gamete formation.

What is the Law of Independent Assortment?

Inheritance of one trait does not affect another.

What is incomplete dominance?

A blended phenotype.

What is codominance?

Both alleles are equally expressed.

How many chromosome pairs do humans have?

23 pairs.

What chromosomes determine sex?

X and Y.

What is the male genotype?

XY.

What is the female genotype?

XX.

Why are X-linked disorders more common in males?

Males only need one recessive allele on the X chromosome.

What is an example of an X-linked trait?

Color blind

What is the main function of the female reproductive system?

To produce gametes (eggs) for reproduction and hormones for female sex characteristics.

What are gametes?

Sex cells such as sperm and egg; they are haploid.

What are somatic cells?

Body cells that are diploid.

What is oogenesis?

The production of eggs via meiosis.

What is a diploid cell?

A cell with two copies of each chromosome.

What is a haploid cell?

A cell with one copy of each chromosome.

How many rounds of division occur in mitosis?

One.

How many rounds of division occur in meiosis?

Two.

What does mitosis produce?

Two identical diploid daughter cells.

What does meiosis produce?

Four genetically different haploid cells.

Where does mitosis occur?

Throughout the body.

Where does meiosis occur?

In the gonads only.

When does oogenesis begin?

Before birth.

What is the primary oocyte?

A diploid cell arrested in prophase I before birth.

What is the secondary oocyte?

A haploid cell arrested in metaphase II until fertilization.

How many ova are produced from one round of meiosis?

One ovum; the other three cells become polar bodies.

What are polar bodies?

Small nonfunctional cells produced during oogenesis that degenerate.

Where does oogenesis occur?

In the ovaries.

What is ovulation?

The release of a secondary oocyte from the ovary.

What is the role of the fimbriae?

To sweep the egg into the fallopian tube.

What are the regions of the fallopian tube?

Infundibulum, ampulla, isthmus.

Why can ectopic pregnancy occur?

Because there is no direct connection between the ovary and the fallopian tube.

What are the three layers of the uterus?

Perimetrium, myometrium, endometrium.

What is the perimetrium?

The outermost layer of the uterus.

What is the myometrium?

The smooth muscle layer of the uterus that contracts during labor.

What is the endometrium?

The inner epithelial lining that sheds during menstruation.