Human Reproductive Systems Our species lives on……. Human Reproduction Part II loUY&feature=related.

Human Reproductive Systems

Our species lives on…….

Human Reproduction Part II

http://www.youtube.com/watch?v=hAgOk3-loUY&feature=related

MALE REPRODUCTIVE SYSTEM

Male Sexual DevelopmentTestosterone is the male reproductive hormoneSecreted in small amounts until puberty

Puberty begins when:Hypothalamus Pituitary increased

FSH and LH GONADS (TESTES)GONADS TESTOSTERONE

Testosterone produces male 2ndary sex characteristics (such as body hair, muscle development, deep voice)

Male Reproductive PartsTestes: Male reproductive gland Sperm and testosterone

produced

Scrotum: Protective sac around testes Keeps testes cool (this keeps

the sperm at an optimum temperature for development

Epididymus: Stores sperm while they

mature

Vas Deferens: Tube that carries sperm from

epididymis to urethra

Diagram of Testicle

Male Reproductive PartsProstate gland -- the largest of several glands which add lubricating and other fluids to the sperm Urethra: tube through the penis carrying sperm to

the outside of the bodyOther glands work together to produce seminal fluid. Combination of sperm and seminal fluid =

semen

2010 Reproduction -SMB

6. penis -- adaptation for internal fertilization of the female

Semen travels from testes →vas deferens→ urethra→ penis → outside of the body through ejaculation (uncontrolled muscle contractions)

Female Reproductive SystemSide view

Female Sexual Development

Estrogen and progesterone are the female reproductive hormones

Puberty begins when:Hypothalamus Pituitary increased

FSH AND LH GONADS (OVARIES)GONADS Estrogen and progesterone

Estrogen produces female 2ndary sex characteristics (broadening of pelvis, breast development, and are involved in the menstrual cycle and pregnancy).

Female Reproductive PartsOvaries: Female Reproductive Gland

(females have two of these) Eggs (ova) produced here Also contain follicles:

Place where eggs mature

Fallopian tubes (Oviduct): Tubes that carry an egg from

ovary to uterus Place of fertilization

Egg Travel: From the ovaries → fallopian tubes/oviducts → uterus


Uterus: Mostly muscle implantation and

development of the embryo and fetus before birth occurs here

Vagina (or birth canal) entry point for sperm from

the male and exit tube for the baby when it is born


HUMAN REPRODUCTIVE SYSTEMS Diagrams….

Fertilization & Development

Types of Fertilization

External: gametes fuse outside the body of the female Occurs in animals that breed in the water (most

invertebrates- Fish/amphibian) The two parents release their eggs into the water, and

the sperm fertilizes the eggs.

Internal – gametes fuse inside the body of a female Fertilization occurs inside the female body

where it is moist Occurs mostly in animals that reproduce on

land and some aquatic animals like sharks, reptiles, and mammals


PROS CONS

EXTERNAL Large numbers of eggs and sperm are released to increase chances of survival.

Gametes released at the same time

Sperm may not find the eggs.

Predators may find and eat eggs or small offspring.

Changes in temperature or oxygen content of the water may cause death.

INTERNAL Fewer eggs need to be released.

Hormones and “mating signals” trigger the release of the eggs and sperm. Ex. Singing, special feathers, and pheromones.

Mating must take place within ~ 24 hours for fertilization to occur

COMPARISONCOMPARISON

DAY 0

When sperm penetrates egg Sperm releases special

enzymes to do this Forms a ZYGOTE Recombination occurs:

Combining of genetic info from both parents

(n=23) (n=23) (2n=46)

Sperm + egg = zygote

Occurs in the oviduct

FERTILIZATION

Multiple births: fraternal twins- 2 eggs identical twins- one egg that

splits in two, always the samehttp://www.brainpop.com/health/

geneticsgrowthanddevelopment/twins/

Abby & Brittany turn 16

http://www.bing.com/videos/search?q=abby+and+brittany+hensel&mid=78A3B27DF1EF569A364278A3B27DF1EF569A3642&view=detail&FORM=VIRE2&adlt=strict

Abby & Brittany Hensel- Conjoined twins (aka Siamese twins) are identical twins whose bodies are joined in utero.

FertilizationFertilization


Occurs in the oviduct Zygote begins a series of mitotic divisions (cleavage) to undergo differentiation Division process is rapid - no increase in size, just the number of cells:

1 cell→ 2 cells→ 4→ 8→ 16→32→64→ 128 …etc

Implantation of zygote in uterus occurs around day 7

Early Development- The First WeekEarly Development- The First Week


EMBRYONIC DEVELOPMENT

Embryonic Layers and FunctionsGASTRULATION

Cells in zygote form into 3 distinct layers

The cells within each layer The cells within each layer DIFFERENTIATE DIFFERENTIATE to formto form specialized specialized cellscells (muscle, liver, heart, etc) then (muscle, liver, heart, etc) then tissue and organs. tissue and organs. This is caused by This is caused by gene activationgene activation

which can be influenced by the which can be influenced by the environment.environment.


EctodermEctoderm MesodermMesoderm EndodermEndoderm

skin and nervou

s system

Muscular, circulatory skeletal, excretory and reproduction systems

lining of digestive and respiratory

tract (body organs)


These developing cells are now called an embryonic stems cells and can be used as for medical research and application

http://www.brainpop.com/science/cellularlifeandgenetics/stemcells/http://www.pbs.org/wgbh/nova/body/stem-cells-breakthrough.html


HUMAN FETAL DEVELOPMENT

1. Placenta – Develops at 3 weeksPlacenta is a fetal organConnects mother and fetusFood, gases and wastes DIFFUSE across blood vessels

2. Umbilical cord- rope-like structure that connects the fetus to the placenta

3. Amnion- membrane surrounding the fetus

4. Amniotic fluid – fills the amnion, protects the fetus, and absorbs shock


Most critical time of development is the 1st trimester when organs are developing

Harmful environmental risk factors include drugs, rugs, alcoholalcohol tobaccotobacco medicinesmedicines poor dietpoor diet, , toxic substancestoxic substances infections infections

This can halt development or cause major developmental issues

Not taking care can result in miscarriage or can severely damage embryo/fetus

First and Second Trimester Dangers!!!!

8 weeks = FETUS

Umbilical cord forms at 3 months

Body systems become more specialized

Fetus becomes bigger

BirthBirth (36 weeks (36 weeks)

Later Development


Human fetal development7 weeks4 weeks


Human fetal development10 weeks


Human fetal development

12 weeks 20 weeks


Human fetal developmentThe fetus just spends much of the 2nd & 3rd trimesters just growing

…and doing various flip-turns & kicks inside amniotic fluid

Week 20


Human fetal development24 weeks (6 months; 2nd trimester)

fetus is covered with fine, downy hair called lanugo. Its skin is protected by a waxy material called vernix


Getting crowded in there!!32 weeks (8 months)

The fetus sleeps 90-95% of the day & sometimes experiences REM sleep, an indication of dreaming


Human fetal development30 weeks (7.5 months)

umbilical cord


The end of the journey!

And you think 9 months of

Biology is hard!

The Menstrual and Ovarian CyclesThe Truth behind PMS!!

Menstrual CycleMenstrual Cycle

Begins at puberty and ends at menopauseTakes about 28 daysRegulated by four hormones: estrogen, progesterone, FSH and LH

MenopauseThe menstrual cycle stops permanently usually between the ages of 45 and 50 although it may occur sooner. The permanent cessation of the cycle is called Menopause.

Vocabulary- Vocabulary- THE HORMONESTHE HORMONES

A. Secreted by the Pituitary gland: FSH (Follicle Stimulating Hormone)

Stimulates follicle to cause egg to mature LH (Luteinizing Hormone)

Causes release of mature ovum (ovulation)

Prepares uterus for implantation of fertilized egg

B. Secreted by Ovaries: Estrogen

Causes uterine lining to thicken Progesterone:

Works with estrogen to finish uterine lining thickening

The CyclesThe CyclesA. Ovarian Cycle:

Occurs over 28 days in the ovaries Process during which an ovum matures in

a follicle and is released during ovulation After ovulation, a corpus luteum (yellow

body) is left behind

B. Menstrual (Uterine) Cycle: Occurs over 28 days Process during which uterine lining is

preparing for fertilized ovum If fertilization occurs, this cycle stops

until after birth If not fertilized, lining sheds

(menstruation!) and cycle begins again

Menstrual Cycle Flow ChartMenstrual Cycle Flow Chart

Menstruation (3-5 days)

•Uterine lining sheds and FSH increases•This causes drop in estrogen and progesterone•Occurs if egg is not fertilized

Menstrual Cycle Flow ChartMenstrual Cycle Flow ChartFollicle Stage: (10-14 days)

•Low estrogen = FSH to be released (negative feedback)•This stimulates growth of follicle •Follicle (egg) matures causing estrogen levels to go up

•Uterine lining begins to thicken again

Menstruation (3-5 days)


Menstrual Cycle Flow ChartMenstrual Cycle Flow ChartFollicle Stage: (10-14 days)Follicle Stage: (10-14 days)



Menstruation (3-5 daysMenstruation (3-5 days)


Ovulation (1 day)Ovulation (1 day)

•Major SPIKE of LH•This causes follicle to break and release egg into oviduct

Menstrual Cycle Flow ChartMenstrual Cycle Flow ChartFollicle Stage: (10-14 days)Follicle Stage: (10-14 days)



Menstruation (3-5 days)Menstruation (3-5 days)


Ovulation (1 day)Ovulation (1 day)

•Major SPIKE of LH•This causes follicle to break and release egg into oviduct

Corpus Luteum Phase (10-14 days)Corpus Luteum Phase (10-14 days)

•LH and FSH levels crash•Corpus luteum forms from broken follicle•Corpus luteum secretes estrogen and progesterone

•This thickens uterine lining to prepare for egg

Negative Feedback: When one hormone is increased it shuts off another hormone

Ex. Glucagon is high, Insulin is Low

What is going on all at once?

Uterus response

Ovary response


REPRODUCTIVE TECHNOLOGYIn vitro Fertilization Process

http://www.youtube.com/watch?v=GeigYib39Rs http://www.sumanasinc.com/webcontent/animations/content/invitrofertilization.html


Directions: READ your review book pageS 71-72. Fill out the blank columns for each of the 4 technologies listed.

Technology Purpose

Agriculture 1.

2.

Ecology 1.

2.

Health Care 1.

2.

3.

Human Reproductive Systems Our species lives on……. Human Reproduction Part II loUY&feature=related.

Documents

human reproduction

male reproductive glandsperm

female body

stores sperm

combination of sperm

eggs ova

internalfewer eggs

semen2010 reproduction