Bio 1114 Study guide for test 1

Reproduction

What is/are?

• Gonads
• Accessory reproductive organs
• Testes
• Ovary
• Scrotum

Dartos muscle – muscle in skin of scrotum

Cremaster muscle – elevate testes

Seminiferous tubules – produce sperm

Interstitial cells – produce testosterone

Cryptorchidism – retained testicles

Why are male gonads outside the peritoneal cavity?

What is a major risk for testicular cancer?

What is circumcision?

Epididymis – for storage of sperm

Ductus deferens (vas deferens) – for sperm transport

What is a vasectomy –

Male accessory glands –

            Seminal vesicles

            Prostrate

            Bulbourethral glands

• Spermatogenesis - formation of sperm

• Gamete - egg or sperm

• Haploid - having only one set of chromosomes such as egg or sperm

• Diploid - having two sets of chromosomes such as normal body cells (somatic cells)

Gametes are formed by meiosis

In meiosis, you start with one diploid cell and get 4 haploid cells.

 Somatic cells are formed by mitosis.

In mitosis, you start with one diploid cell and get 2 diploid cells.

 For meiosis, you start with one diploid cell and get 4 haploid cells.

How many chromosomes do humans have?  (46, 23 pairs)

 Sertoli cells – protect developing sperm from the immune system

Brain/testicular axis

1.  Hypothalamus in brain releases GnRH

2.  This causes the pituitary to release FSH and LH

3.  FSH cause spermatogenesis

4.  LH causes testosterone secretion

5.  When testosterone level is adequate, it inhibits further GnRH release.

What are some of the secondary sexual characteristics of male humans?

Oocyte – immature egg

Ovarian follicle – sac-like structure on outside of ovary that contains oocyte

Corpus luteum – glandular structure that remains after follicle ruptures, produces hormones to maintain pregnancy in early stages

 Fallopian tubes = oviducts = uterine tubes – carry egg from ovary to uterus; fertilization takes place here

 Ectopic pregnancy

 Pelvic inflammatory disease

 Uterus

Cervix

What is a major cause of cervical cancer?  (human papilloma virus)

What is prolapse of the uterus?

Perimetrium – outer layer of uterus

Myometrium – middle, muscular layer of uterus

Endometrium - inner lining of uterus

Vulva – female external genitalia

• Hymen
• Perineum

Mammary glands

            Present in both sexes (only function in females)

            Part of the integument

            Modified sweat glands

Areola – pigmented area around nipples

Note: humans have nipples, not teats. Cattle have teats which are elongated structures.

 Mammography – x-ray of mammary glands

 Lactation – milk production

Toward the end of pregnancy

• Hypothalamus releases PRH
• Pituitary release prolactin
• Prolactin stimulates milk production
• Oxytocin is released as nerve impulses from nipple stimulate the posterior pituitary
• Oxytocin causes milk let down.

Colostrum – first milk, rich in antibodies and nutrients

Oogenesis – egg production

In spermatogenesis, you get 4 sperm

In oogenesis, you get one egg and 3 polar bodies (duds)

Ovarian Cycle

1. Hypothalmus release GnRH
2. GnRH causes anterior pituitary to release FSH and LH
3. FSH stimulates follicles to develop  (that’s why it’s called follicle stimulating hormone)

(meanwhile, the endometrium is developing to get ready for the pregnancy)

4. LH causes estrogen production
5. High estrogen level causes burst of LH hormone
6. High level of LH causes ovulation
7. LH causes development of corpus luteum (that’s why it’s called luteinizing hormone)
8. If there is no pregnancy, the corpus luteum degenerates, and the endometrial lining is sloughed off.  (Menstrual period)

Amenorrhea – stopping having periods

Libido – sex drive

            In male- caused by testosterone

            In female – caused by androgens from the adrenal glands

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1. Testicle

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2. Ovary

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3. Spermatogenesis

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4.  Follicle development

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5.  testosterone production

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6.   estrogen production, ovulation, formation of corpus luteum

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