1. Embryonic Differentiation & Development

2. Path of the sperm & egg to fertilization & implantation
Produced in semeniferous tubules of the testes
Move to epididymis for maturing
Through the vas deferens
Out the urethra
Into the vagina
Through the cervix
Through the uterus
Into oviduct
Egg:
Produced in follicle of the ovary
Released into the oviduct
Fertilization: occurs in the oviduct.
Implantation: occurs in the endometrium of the uterus after the zygote travels down the oviduct

3. Identical vs. Fraternal twins
Identical twins arise from 1 egg/sperm combination & during cleavage the zygote splits into two producing two zygotes with identical DNA
Fraternal twins arise when two eggs are fertilized but two separate sperm.

4. Identical vs. Fraternal twins
If a lady has quintuplets what possible combinations of fraternal & identical are there?

5. Basic Stages of embryonic development 1) morula 2) Blastocyst 3) Gastrula 4) Neurula

6. Basic Stages of embryonic development
Morula: mass of identical cells resulting from cleavage. Each cells become smaller and size of the ball does not increase
Blastocyst: as cleavage continues the ball of cells becomes hollow and contains an inner mass of cells
Gastrula: When cells begin to specialize and form germ layers.
Neurula: As Gastrula develops it forms a neural tube

7. Basic Stages of embryonic development other definitions p. 507-508
Cleavage: cell division without growth
Trophoblast: outer layer of cells around the blastocyst which will form the placenta & Umbilical cord
Embryo: time from cleavage starts until bone forms.
Germ layers: three layers in gastrula endoderm, Mesoderm, ectoderm

8. Primary membranes of embryonic development

9. Primary membranes of embryonic development p. 508
Chorion: involved in gas exchange
Amnion: contains the amniotic fluid
Allantois: collects waste
Yolk: provides nutrients

10. Placenta & Umbilical Cord p. 510
Umbilical cord connects the fetus to the placenta via arteries and veins allowing waste out to mothers blood and receiving nutrients from mothers blood
Placenta: forms from the chorion. Blood vessel rich organ with branches that project into the uterine wall.(chorionic villi) Maternal blood and fetus blood never mixes. Nutrients are passed by diffusion

11. Cigarette smoke, alcohol and thalidomide are all known teratogens
Teratogens p. 511
Teratogens: any substance that causes a physical abnormality in the development of the fetus
Cigarette smoke, alcohol and thalidomide are all known teratogens
Cigarette smoke constriction of blood vessels, low body weight and convulsions
Alcohol causes (FAS) decreased weight, height and head size, mental retardation & agression
Thalidomide was given to pregnant women to reduce morning sickness but it caused missing and deformed limbs

12. Child Birth in Humans p. 512-513

13. Child Birth in Humans p. 512-513
Dilation Stage: uterine contractions and oxytocin cause cervix to dilate. Amniotic sac breaks Expulsion stage: forceful uterine contractions force baby through the birth canal Placental Stage: placenta and umbilical cord are expelled minutes after the baby and is known as “after birth”.

14. Hormones after birth p. 513-514
Estrogen & progesterone were high during pregnancy and inhibited prolactin production. After birth estrogen and progesterone decrease allowing prolactin to be produced. Prolactin is produced by the anterior pituitary and stimulates mammary glands to produce milk. Suckling is detected by anterioir pituitary which produces oxytocin. Oxytocin causes contraction of the mammary gland to force milk out the mamary duct

15. Fertilization in Flowers p. 175

16. Fertilization in Flowers p. 175
Pollen grain contains a tube nucleus & generative nucleus. Tube nucleus digs the pollen tube down to the micropyle (hole in the ovule). Generative nucleus forms 2 sperm nuclei. One fertilizes the egg forming the embryo. The other joins with 2 haploid nuclie to form the 3n endosperm (food source for the seed.

17. Monocot seeds vs. dicot seeds p. 175
Monocot seeds have one seed leaf while dicot seeds have two seed leaves