Reproductive System AP Biology Reproductive hormones Testosterone HORMONE

Reproductive System AP Biology

Reproductive hormones Testosterone (HORMONE) � u u from testes sperm production & sex characteristics Estrogen (HORMONE) � u u from ovaries egg production, preparing uterus for fertilized egg & sex characteristics Regents Biology

Male reproductive system � Sperm production over 100 million produced per day! Regents u Biology ~2. 5 million released per drop! u

Male reproductive system � Testes & epididymis u � Glands u � Regents Biology sperm production & maturation seminal vesicles, prostate, bulbourethal (Cowper’s Gland) Semen-produce white seminal fluidnutrient-rich

Male reproductive system � Testicles u � Scrotum u � where sperm mature- 18 hrs Vas Deferens u � sac that holds testicles outside of bodymaintains lower temperature Epididymis u � produces sperm & hormones (testosterone) tubes for sperm to travel from testes to penis Prostate, seminal vesicles, Cowper’s (bulbourethal) glands u nutrient rich fluid to feed & protect sperm Regents Biology

Testis and Spermatogenesis Regents Biology

seminiferous tubule spermatocytes Regents Biology

� Spermatozoa u Head contains nucleuscontains enzymes that help the sperm enter the egg. body and tail allow movement � Mitochondriaprovides ATP for movement (cellular respiration) � Regents Biology

Female reproductive system Regents Biology

Female reproductive system � � � Ovaries- have 2 u produces eggs & hormones- estrogen & progesterone Uterus u Site for fetal development, nurtures fetus; lining builds up each month- menstruation- shedding of the lining of the uterus. Fallopian tubes/Oviduct- 2 u tubes for eggs to travel from ovaries to uterus u Fertilization occurs in the fallopian tubes Cervix u (separates vagina from uterus) opening to uterus, dilates 10 cm for birthing baby Vagina u birth canal for birthing baby; sperm enter here Regents Biology

Female reproductive system Regents Biology

Egg maturation in ovary releases progesterone maintains uterus lining produces estrogen Regents Biology

LH Menstrual cycle � Controlled by interaction of 4 hormones FSH Ovulation = egg release from Ovary FSH & LH egg development u estrogen u progesterone u corpus luteum progesterone Uterine Lining Changes with Hormones Regents Biology Days: 0 7 14 21 28

Feedback Female reproductive cycle egg matures & is released (ovulation) estrogen builds up uterus lining corpus luteum ovary progesterone FSH & LH maintains uterus lining fertilized egg (zygote) yes pituitary gland pregnancy Gn. RH Regents Biology hypothalamus no corpus luteum breaks down progesterone drops menstruation HCG corpus luteum progesterone maintains uterus lining

Female hormones � FSH & LH u u � Estrogen u u � stimulates egg development & hormone release peak release = release of egg (ovulation) stimulates growth of lining of uterus and egg development decreasing levels causes menstruation Progesterone u u stimulates blood supply to lining of uterus decreasing levels causes menstruation Egg= Ova/Ovum (singular) Regents Biology

Events for Sexual Reproduction in Humans � � Sexual Intercourse- male sperm enter the female vagina during intercourse. Sperm swim past the vagina and uterus into the fallopian tubes where the egg is located. Fertilization- process where sperm enters and fertilizes egg (ovum)- resulting in the formation of a zygote Regents Biology

Zygote- fertilized egg undergoes mitosis (cleavage) to make more living cells. Now called an EMBRYO ( ball of body cells). � Differentiation/Specialization- process where new cells specialize and become different from one another to produce different tissues, organs and organ systems. � Regents Biology

Fertilization 2. Differentiation- Different cells and tissues will develop into organs in body systems. 1. Zygote Embryo Regents Biology

***If the mother consumes alcohol or uses drugs during the first trimester (first 3 months of pregnancy), the developing baby can be harmed more since differentiation is occurring during this time period (compared to later on in pregnancy). *** Regents Biology

Sex Determination in Mammals Regents Biology

Twins � Identical Twins- ONE fertilization u Zygote splits into two with each being identical to one another Regents Biology

§Fraternal Twins- TWO fertilizations §Two different zygotes (different egg and sperm) Regents Biology

� Siamese Twins- identical twins whose bodies fail to fully separate- and stay joined together Regents Biology

Regents Biology

Placenta & umbilical cord � � Allows for nutrients and gases to be exchanged between mom and child Food & gases diffuse across blood vessels ~Blood of mom and child does not mix! B B Regents Biology

Human fetal development At 9 weeks officially called a fetus 4 weeks Regents Biology 7 weeks

Human fetal development 10 weeks Regents Biology

Human fetal development 12 weeks Regents Biology 20 weeks

Human fetal development � The fetus just spends much of the 2 nd & 3 rd trimesters just growing …and doing various flip-turns & kicks inside amniotic fluid Week 20 Regents Biology

Human fetal development � 24 weeks (6 months; 2 nd trimester) fetus is covered with fine, downy hair called lanugo. Its skin is protected by a waxy material called vernix Regents Biology

Human fetal development � 30 weeks (7. 5 months) umbilical cord Regents Biology

Getting crowded in there!! � 32 weeks (8 months) The fetus sleeps 90 -95% of the day & sometimes experiences REM sleep, an indication of dreaming Regents Biology

Positive Feedback Birth Regents Biology

Birth (37 -40 weeks) Intestine Placenta Umbilical cord Wall of uterus Bladder Cervix Vagina Regents Biology

The end of the journey! And you think 9 months of Biology is hard! Regents Biology

Harmful Environmental Factors � Embryo’s inherited genes can cause diseases u � � Mutations- changes in DNA (DNA makes up chromosomes) Mother’s exposure to harmful environmental factors such as DRUGS, POOR DIET, ALCOHOL, TOBACCO can cause developmental problems and learning disabilities. 1 st TRIMESTER Most Important (organs develop) Sexually Transmitted Diseases (STDs)- diseases passed on from person to person through sexual contact u AIDS, Chlamydia, Syphilis Regents Biology

Let’s Practice! 1. Which statement about the gametes represented in the diagram below is correct? 1. 2. 3. 4. They are produced by females. They are fertilized in an ovary. They transport genetic material. They are produced by mitosis. Regents Biology

1. 2. 3. 4. 2. Base your answer on your knowledge of biology and on the diagrams. Testosterone is produced by structure A structure B structure C structure D Regents Biology

3. Base your answer to this question on the diagram below, which represents some stages in the development of an embryo, and on your knowledge of biology. The arrow labeled X represents the process of 1. 2. 3. 4. meiosis recombination differentiation cloning Regents Biology

1. 2. 3. 4. Base your answer on the diagram and your knowledge of biology. Gamete cells are produced within structures A and J structures E and G structures B and I structures D and H Regents Biology

1. 2. 3. 4. 5. The diagram represents some stages in the development of an embryo. Which stage represents a zygote? stage A stage B stage C stage D Regents Biology

6. The primary function of structure X is to 1. 2. 3. 4. produce energy needed for sperm to move provide food for the sperm to carry to the egg produce and store urine form gametes that may be involved in fertilization Regents Biology

7. Although all the body cells in an animal contain the same hereditary information, they do not all look and function the same way. The cause of this difference is that during differentiation 1. 2. 3. 4. embryonic cells use different portions of their genetic information the number of genes increases as embryonic cells move to new locations embryonic cells delete portions of the chromosomes genes in embryonic cells mutate rapidly Regents Biology

8. Which hormone has the lowest concentration on which day? 1. 2. 3. 4. hormone A on day 4 hormone B on day 2 hormone C on day 12 hormone D on day 20 Regents Biology

9. Human egg cells are most similar to human sperm cells in their 1. 2. 3. 4. degree of motility amount of stored food chromosome number shape and size Regents Biology

1. 2. 3. 4. 10. During which five-week period did the fetal mass increase at the greatest rate? weeks 10– 15 weeks 15– 20 weeks 25– 30 weeks 30– 35 Regents Biology

11. The process of meiosis formed 1. 2. 3. 4. cell 1, only cells 1 and 2 cell 3, only cells 2 and 3 Regents Biology

12. Heavy cigarette smoking and the use of alcohol throughout pregnancy usually increase the likelihood of 1. 2. 3. 4. the birth of twins the birth of a male baby a baby being born with a viral infection a baby being born with medical problems Regents Biology

13. A large number of sperm cells are produced by males every day. This large number of sperm cells increases the chance that 1. 2. 3. 4. at least one sperm cell will be reached when the eggs swim toward the sperm cells in the ovary several sperm cells will unite with an egg so the fertilized egg will develop properly some of the sperm cells will survive to reach the egg enough sperm cells will be present to transport the egg from where it is produced to where it develops into a fetus Regents Biology

1. 2. 3. 4. 14. Exposure to radiation or certain chemicals could alter the genetic information in the gametes that form in structure A B C D Regents Biology

15. Which event would most probably result in the production of fraternal twins? 1. 2. 3. 4. One egg is fertilized by two sperm cells. Two egg cells are fertilized by one sperm cell. Two egg cells are each fertilized by separate sperm cells. Two eggs develop without fertilization. Regents Biology

16. Compared to human cells resulting from mitotic cell division, human cells resulting from meiotic cell division would have 1. 2. 3. 4. twice as many chromosomes the same number of chromosomes one-half the number of chromosomes one-quarter as many chromosomes Regents Biology

17. Which phrase best describes a process represented in the diagram below? 1. 2. 3. 4. a zygote dividing by mitosis a zygote dividing by meiosis a gamete dividing by mitosis a gamete dividing by meiosis Regents Biology

18. A cell with a diploid chromosome number of 12 divided two times, producing four cells with six chromosomes each. The process that produced these four cells was most likely 1. 2. 3. 4. internal fertilization external fertilization mitotic cell division meiotic cell division Regents Biology

19. Which structure is correctly paired with its function? 1. 2. 3. 4. A - releases estrogen and progesterone B - produces and releases the egg C - provides the usual site for fertilization D - nourishes a developing embryo Regents Biology