Class Notes (836,147)
United States (324,358)
ANT 2301 (23)

Sexual Characteristics

5 Pages
Unlock Document

ANT 2301
Geoffrey Thomas

ANT NOTES 09-10/12  PRIMARY SEXUAL CHARACTERISTICS o Genitals (sex organs)  Male- penis and testicles  Female- vagina, cervix, uterus, ovaries  FERTILIZATION o Process involves a sperm fusing w/ an ovum o Sperm burrows through the outer jelly coat of the egg o Sperm plasma then fuses with the egg’s plasma membrane, sperm head disconnects from it flagellum and the egg travels down the fallopian tube to reach the uterus  EMBYOIC DEVELOPMENT o Week 1-3  5-7 days after fertilizations, blastula attaches to wall of uterus and forms the umbilical cord  Embryo’s growth centers around an axis- becomes spine and spinal cord  Brain, spinal cord, heart, and gastrointestinal tract begin to form o Week 4-5  Menstrual cycle stops  Tissue formation occurs that develops into the vertebrae and some bones  Heart starts to beat and blood starts to flow o Week 6-8  Brain activity begins  Embryo capable of motion  Eyes begin to form  Facial features begin to develop  FETAL STAGE o Fetal period begins at the end of the 10 week of gestation or the 8th week of development o Fetus isn’t as sensitive to damage from environmental exposures as the embryo because precursors of the organs have formed  Toxic exposures often cause physiological abnormalities or minor congenital malformation  EXTERNAL GENITALIA o Until about 9 week of gestational age, external genitalia of males and females look the same o Sex dependent development includes further protrusion of the genital tubercle in the male to form the penis o The labioscrotal folds evolve into the scrotum in males and the labia in females  INFANT DEVELOPMENT o Fully equipped at birth  Ultrasounds have shown male fetuses w/ erections in th uterus and shortly after birth  Female babies capable of vaginal lubrication from birth  Both sexes produce very small amounts of estrogen and testosterone from birth  CHILD DEVELOPMENT o Early Childhood (2-5 years)  Crucial period of physical development  Hand eye coordination, walking and talking  Begin exploration of their bodies o During potty training  What is a boy/girl?  Might engage in sex play (don’t know what it is)  MIDDLE CHILDHOOD DEVELOPMENT o 6-12 years  sex organs grow in size along w/ rest of the body o overt sexual behavior becomes more private  now know what is appropriate to their culture o begin asking about birds and the bees  no more stork answers  MALE PUBERTY o Changes in primary characteristics o Male gonads show maintained growth w/ rest of the bod until puberty o Size of testes and scrotum rapidly increase o Rate and timing vary between ages of 10 and 18 yrs o Penis grows in both length and garth steadily through childhood o Followed by rapid increase in size beginning at puberty o Testes main function- produce male sex hormones and sperm  Around 10, the hypothalamus begins releasing gonadotropin releasing hormone  ^ This stimulates follicle-stimulating hormone and luteinizing hormone  Stimulates the produc. Of testosterone which results in sperm production  FEMALE PUBERTY o Changes in primary characteristics  S low progression and growth until puberty  Ovaries are small, undeveloped, and functionally immature  At puberty eggs begin to ripen  One app. Every 28 days or every menstrual cycle  Enters fallopian tube and passes into uterus  Passes through vagina to outside genital opening  ^first definite indication that a young girl has to inform her of her sexual maturity in menarche, or first menstruation  MENARCHE o Pituitary gland begins secreting follicle-stimulating hormone and luteinizing hormone o ^Stimulates ovaries to produce estrogen o The increase secretion of estrogen cause maturation and growth of fall
More Less

Related notes for ANT 2301

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.