Tuesday, March 23, 2010
Tues-Day 1
Bio - On Blackboard, I posted animations of each step of meiosis- great for review- check them out!
HW Objectives due tomorrow, Wednesday. Final test of the THIRD QUARTER on Friday, vacation begins Saturday.
HW Objectives due tomorrow, Wednesday. Final test of the THIRD QUARTER on Friday, vacation begins Saturday.
In Objective 8, "somatic cell" is ANY cell in the body EXCEPT a GAMETE/SEX CELL/SPERM/EGG - answer this objective.
In Objective 20, "spermatogenesis" means "making sperm cells", and "oogenesis" means "making an egg cell"; answer the objective.
The answers to Objectives 22 - 24 are DIRECTLY in today's notes.
We did not get to the following objectives, so you can omit the following from your homework:
Objective 2 - I don't remember specifically discussing the purpose of ejaculation but, naturally, that process propels the sperm into the vagina so that the sperm can swim to the oviducts to possibly fertilize an egg.
Objective 6 - gestation is the length of time that an embryo/fetus develops in the uterus until the baby/offspring is born. Humans have a 39 week gestation period, on average. Dogs have an 8 week gestation period to develop puppies.
IN VITRO fertilization takes place in a test tube or any kind of compartment outside of a live female; typically, sperm and eggs are mixed in a test tube to cause fertilization; then the fertilized egg/embryo is implanted in a female's uterus. This procedure is used when a female has damage to her oviducts that would prevent fertilization there (known as IN VIVO, literally "inside a living person").
Objective 7: the production of either sperm or egg, gametes/sex cells, from primary sex cells via meiosis.
Objective 12: Gonads are the organs that make the gametes/sex cells: ovaries in females and the testes in males.
Omit Objective 25 - notes on that will be given tomorrow.
We looked at sex cell creation/ gametogenesis via meiosis in both males and females, paying particular attention to the TWO main sources of variety in DNA/allele combinations : 1. crossing over during prophase I and 2. independent assortment of chromosomes during metaphase I. We also examined how the DIPLOID number of chromosomes in the PRIMARY sex cells is HALVED as the sperm or egg is formed.
We then discussed the development of the embryo that is attached to the uterus: after fertilization, MITOSIS occurs so that the embryo forms a BALL of cells, the blastula which eventually turns into a THREE-LAYER mass of cells, the GASTRULA. We discussed how cell differentiation and specialization causes each layer to DEVELOP into particular organs/organ systems. Inner layer cells form inner organs, middle layer cells form middle layer organs, and outer layer cells form outer layer organs.
We then did worksheets on meiosis and a comparison or meiosis and mitosis.
AP Chem - we derived the Henderson-Hasselbalch equation for basic buffers and then did a problem in which a solution of a Bronsted base and a solution of the salt of the base's conjugate acid were mixed.
# posted by C @ 1:11 PM 
