HUMAN REPRODUCTION AND DEVELOPMENT Handout #22

The Male Reproductive System- Sperm production occurs in the ______ that is enclosed by the scrotum. This is outside of the body because ° Celsius is optimum for male gamete production. Testes

Sperm leaves the testes and travel through the ___ ________. Along the way, glands secrete liquids to add to the sperm, and the liquid plus sperm is called ______. The ______ passes out of the body through the same tube as urine leaves. A valve closes during ejaculation a valve closes so urine does not contaminate the semen semen semenVasdeferens

Remember the testis also produce the hormone __________, which regulates the development of the male secondary sex characteristics testosterone

Secondary Sex Characteristics

The Female Reproductive System- Egg production occurs in the ______ of the female. Inside the ovaries are many follicles that contain egg cells, or____.ovaries ova

Once a month, a follicle ruptures and burst. This is called ________. The egg travels from the ovary through the _______, or fallopian tube to the ______. If sperm are present in the oviduct, fertilization may occur, and embryonic development takes place in the uterus. ovulation oviduct uterus

From Ovulation to Implantation

If there is no fertilization, the egg degenerates. The uterus opens into the _____, which opens next into the ______, or birth canal. Remember the ovaries produce two hormones, _______ and ___________, in addition to eggs. cervix vagina estrogen progesterone

Menstrual Cycle The female reproductive cycle the lining of the ______ prepares for implantation of the blastula and thickens and becomes __________, which means filed with blood vessels. If there is no fertilization, the lining breaks down and the material is expelled and the cycle begins again. uterus vascularized

Menstrual Cycle cont. This begins at _______, the stage at which an individual becomes capable of reproducing. __________ is the time when the menstrual cycle stops. The whole cycle is regulated by _________ and lasts for 28 days. The Menstrual Cycle has 4 stagespuberty Menopause hormones

1. Follicle Stage During this stage, the egg matures and the follicle secretes ________ to stimulate the thickening of the uterine lining. ___ from the pituitary gland stimulates this to occur. This lasts for _____ days estrogen FSH

2. Ovulation This occurs about midway in the cycle. The egg is released! This inhibits ____ from the pituitary, and __ is secreted from the pituitary to take care of the place left where the egg was in the ovary. It is in this stage that FERTILIZATION can occur. If fertilization does not occur within 24 hours the egg degenerates. FSH LH

3. Corpus Luteum This forms at the ruptured follicle. ____________ is secreted to continue the _____________ of the uterine lining. This lasts for about ___ days. If the egg is NOT fertilized, stage 4 occurs. Progesterone vascularization 12

4. Menstration The lining breaks down, and the lining and the egg pass ut of the female’s body. This lasts for __to __ days. This cycle stops temporarily during _________ and permanently at __________. 24 pregnancy menopause

Diagram:

Hormones and Menstruation The pituitary gland releases ____ to stimulate a follicle to develop. As the follicle develops, it secretes ________, which causes ovulation and vascularization. (__ estrogen: __ FSH) **Negative Feedback** **Birth Control Pill**FSH estrogen  

The pituitary gland releases ___ which causes the formation of the corpus luteum, and ___________ is secreted by the ovaries. (__ progesterone: __ LH) (__ LH: __ progesterone) The uterine lining thins out, and menstruation occurs. If fertilization does occur, the ______ undergoes (______), forms a blastula, and then a _______, then differentiates and the placenta, umbilical cord, and the amnion form.LH progesterone    zygote mitosis gastrula

In Vitro Fertilization- This is when fertilization occurs _______ the female’s body. Then the early embryo is implanted into the uterus to complete development. (See diagram on next page)outside

Fraternal Twins- - When __ eggs are released at the same time, and both are fertilized (each by a different sperm). They may be the same sex or opposite sexes. They are no more alike than regular brothers and sisters.2

Identical Twins- - When a ______ separates into 2 equal halves early in cleavage. They develop from ___ zygote. They may be the same sex or opposite sexes. They have identical genetic make- ups. They are always the same sex. Why? zygote 1

Birth- Gestation period - _________________ _________________ For humans, it is ___ weeks, or ___ lunar months. At the end of pregnancy progesterone decreases, _______ is secreted by the pituitary gland to begin contractions of the uterus, the amnion bursts, and the baby is born. Postnatal Development: childhood, puberty, adulthood, old age. The time between fertilization and birth 4010 oxytocin