Reproductive System

1. Reproductive System Michelle Boyken Margaret Huffines Devan Daugherty Alyssa Henson

2. What Is Reproduction? • The natural process among organisms by which new individuals are generated • Purpose is to ensure the survival of species and pass on our own genetic identity

3. Types of Reproduction Asexual Sexual • creation of offspring from a single person • does not involve the joining of gametes • involves the joining of gametes • allows a person to be unique with their own special characteristics and traits

4. Types of Fertilization Internal External • Sperm fertilizes egg within the female • Oviparity- egg laid outside the female body • ovoviparity- egg is held within the female • viviparity- development within the female is followed by live birth • Release of both sperm and eggs into an external environment • sperm will fertilize the egg outside of the organism

5. Female Anatomy • Fallopian tube- tubes connecting the ovaries to the uterus • carry eggs from ovaries to uterus for fertilization • Ovaries- small, oval-shaped glands on both sides of uterus. • produce eggs and hormones • Uterus (womb)- home for developing fetus • Vagina- canal that joins cervix to the outside of the body. • Also called the birth canal

6. Female Anatomy Cont. • Cervix- narrow necklike passage forming the lower end of the uterus • Myometrium- the smooth muscle tissue of the uterus • Endometrium- mucous membrane lining the uterus. • thickens during the menstrual cycle in preparation for possible implantation of an embryo

7. Male Anatomy • Penis- male organ for sexual intercourse. • Scrotum- loose pouch-like sac of skin that hangs behind the penis. • Testicles- oval organs that lie in the scrotum, secured at either end by a structure called spermatic cord. • Urethra- tube that carries urine from bladder to the outside of the body

8. Meiosis • special type of cell division necessary for sexual reproduction in eukaryotes, such as animals, plants and fungi • Number of sets of chromosomes undergoing meiosis is ½ the original # • 2 sets- diploid and haploid • Cells produced by meiosis are gametes • called sperm in males; egg cells in females • B/c meiosis halved the # of sets of chromosomes, when the 2 gametes fuse during fertilization, # of sets of chromosomes in resulting zygote is restored to original #

9. Reproductive Cycles Menstrual Estrous • Humans & Primates • prepares and releases the egg for fertilization • prepares the uterus to receive a fertilized egg • can be sexually active even when not ovulating • Other mammals • no menstruating • usually lasts until death • sometimes have bloody discharge mistaken for menstruation • usually only sexually active during estrous phase of their cycle

10. Terms • Regeneration: • growth of lost or destroyed parts or organs • Parthenogenesis: • a type of reproduction, occurring in some insects and flowers, in which the unfertilized ovum develops directly into a new individual • Hermaphroditism: • an individual animal or flower that has both male and female reproductive organs • Peromone: • chemical that is secreted by an animal, especially an insect, and that influences the behavior or development of others of the same species

11. Spermatheca • holding place in females for sperm • allows females to produce offspring when it’s best for them and without needed to mate at that moment • allows the female to choose the sperm she prefers for the characteristics she desires • makes reproducing easier when organisms are scattered across an environment

12. Embryos • An unborn or unhatched offspring in the process of development • Eutherian mammals: • embryo of placental mammal develops in the mother’s uterus for longer gestational period than the embryo of a marsupial • Marsupial: • born sooner than a placental mammal • less developed than a placental mammal • newborn marsupial must continue its development in a mother’s pouch

13. Importance of Mammary Glands • Produce the mother’s milk to nurture their young (breasts) • the children need their mother’s milk to survive until they are able to eat the typical food their species consumes

14. Vasocongestion and Myotonia Vasocongestion Myotonia • filling of a tissue with blood • increased muscle tension • Vasocongestion and myotonia occurring in men causes erections • In women, external changes cause clitoris to become erect by vasocongestion. Nipples become erect because of myotonia.

15. Foreign Body • A woman’s body doesn’t reject an embryo as a foreign body • The pathway required for the immune system to attack the embryo is shut off

16. Characteristics of Semen That Help In Survival • Inside of vagina is very acidic and hostile • Seminal Plasma- • contains organic & inorganic substances • provides nutrients & protection as semen travels through female • alkaline bases in seminal plasma are what counteracts and compensates for the acids inside the vagina • Bulb urethral Glands- creates a less vicious channel for sperm cells to swim through • also contributes to the texture of semen

17. QUIZ TIME!!! :D