HUMAN REPRODUCTION

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The process of meiotic cell division in a human male usually forms

1. one diploid cell, only

2. four diploid cells

3. one monoploid cell, only

4. four monoploid cells

Castle learning “Reproduction”

Structure that is responsible for storing sperm before leaving the organism

•A.K.A. sperm ducts

•Tube used for sperm transport

•Merges with the urethra

A tube that is responsible for two functions:

1.Elimination of urine

2.Elimination of semen

Leads to the outside of the body

Located in the center of the penis

Male sex organ

Extends off of the lower abdominal cavity

Consists of erectile tissue

Function – deposition of the semen inside the female reproductive tract

?????

Produce and secrete a nutrient rich fluid called seminal fluid

When the sperm and the seminal fluid combine it forms a fluid known as semen

Which process is represented by the diagram?

1. fertilization

2. production of gametes

3. cloning

4. evolution

A male sex hormone is produced within

1. structure A

2. structure B

3. structure E

4. structure F

When asked to relate the terms

sperm, scrotum, testes, and

zygote, a student wrote the

statements below.

(A) They all contain homologous pairs of chromosomes.

(B) The location of the testes within the scrotum aids in the production of sperm needed for zygote formation.

(C) Mitotic cell division in involved in the formation of the testes and scrotum, and meiosis is involved in the production of sperm, which is involved in the formation of a zygote.

(D) Formation of the testes, scrotum, and sperm occurs in human males; zygote formation occurs in females.

Which statements are correct?

1. A, B, and D, only

2. B, C, and D, only

3. B and D, only

4. A, B, C, and D

Castle learning “Reproduction”

Reproductive systems

Two versions:

•Male reproductive system

•Female reproductive system

The term gonads refers to the ovaries in females and testes in males

Do Now:

Label the diagrams below

•Are egg-producing reproductive organs

• often found in pairs

•Ovaries in females are homologous to testes in males

Ovaries are oval shaped and, in the human, measure approximately 3 cm

•Contain approximately 250,000 immature eggs, called follicles, at birth

•Once follicles mature and are released they are called ova/ovum.

A.K.A. oviducts and uterine tubes two very fine tubes leading from the ovaries of female mammals into the uterus

In humans, the Fallopian tubes are about 7–

14 cm long and as “thick” as three strands of hair

Function: Transport egg to the uterus

•A.K.A. the womb

•Muscular organ

•Connected to the fallopian tubes and the vagina

• Outside of pregnancy, its size in humans is several centimeters in diameter

•The main function of the uterus is to accept a fertilized ovum which becomes implanted into the uterine wall

•derives nourishment from blood vessels for the developing embryo

The cervix is the lower, narrow portion of the uterus where it joins with the top end of the vagina

During menstruation the cervix stretches open slightly to allow the uterine wall to be shed

During childbirth, contractions of the uterus will dilate the cervix up to 10 cm in diameter to allow the fetus to pass through.

A.K.A. Birth Canal is a fibromuscular tubular tract leading from the uterus to the exterior of the body in female mammals

Functions: acts as a canal for fetus to exit the mother and location for semen to be deposited

Summary

• Which two glands in the diagram produce gametes?

• glands

A

and

B

• glands

B

and

E

• glands

C

and

F

• glands

E

and

F

This structure releases estrogen into the circulatory system.

1. structure 1

2. structure 2

3. structure 3

4. structure 4

5. structure 5

Menstruation involves the periodic shedding of the lining of

1. Structure 1

2. Structure

2

3. Structure 3

4. Structure 4

DID YOU KNOW>>>the ovum is the largest cell of the body (with a diameter of about 0.5 mm)

Reviewbook pg. 66 #11-21

is a recurring cycle of physiologic changes that occurs in reproductive age females of several mammals

Named is derived from the latin word menses which means month

The menstrual cycle is under the control of the hormone system and is necessary for reproduction

The Endocrine system

The menstrual cycle may be divided into several phases. The length of each phase varies from woman to woman and cycle to cycle.

Phases of the menstrual cycle

• Menstruation

• Follicular phase

• Ovulation

• Luteal phase

•Menstruation is also called menstrual bleeding , a period

•regular menstruation that lasts for a few days usually 3 to 5 days

•the average blood loss during menstruation is 35 milliliters

1. the lining of the uterus thickens

2. stimulated by gradually increasing amounts of estrogen

3. Follicles in the ovary begin developing

4. after several days one or occasionally two follicles become dominant (non-dominant follicles atrophy and die)

5. The dominant follicle releases an ovum or egg in an event called ovulation

1. When the egg has matured, it triggers the release of luteinizing hormone (LH).

2. In the average cycle this LH surge starts around cycle day 12 and may last 48 hours.

3. The release of LH matures the egg and weakens the wall of the follicle in the ovary. This process leads to ovulation : the release of the now mature ovum

4. The egg is swept into the fallopian tube

After ovulation, the residual follicle transforms into the corpus luteum

The corpus luteum is the solid body formed in the ovaries

This corpus luteum will produce progesterone in addition to estrogens for approximately the next 2 weeks

Progesterone plays a vital role in preparing the uterine wall to wither support a pregnancy or to be secreted

In the absence of a pregnancy, progesterone levels fall. This will set the stage for the next cycle…..

Progesterone withdrawal leads to menstrual shedding

If fertilization of an egg has occurred, it will travel to the uterine cavity and implant itself

6 to 12 days after ovulation.

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