{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Development Spring 2009 PV

Development Spring 2009 PV - Biological Development...

Info iconThis preview shows pages 1–19. Sign up to view the full content.

View Full Document Right Arrow Icon
Biological Development
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Endocrine Messengers Hormones : Chemical messengers released into the bloodstream to exert an effect on a distant target. Pheromones : Chemicals released into the environment to act on members of the same species.
Background image of page 2
Major Endocrine Structures Hypothalamus-Pituitary: “Master Gland” Metabolism Thyroid: metabolism, growth, Adrenals: carbohydrate metabolism Pancreas: regulates sugar metabolism via insulin release. Sexual development and behavior: Gonads (Testes, Ovaries)
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Hypothalamus Anterior Pituitary Target Organ Releasing Factor “Triggering” Hormone Sex Hormones (Into Bloodstream)
Background image of page 4
When you were just a twinkle in your daddy’s eye…
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Gonadotropin Effects in Males: LH surge increases the production and release of T from the testicles. FSH surge fuels spermatogenesis. The production of mature male gametes
Background image of page 6
Gonadotropin Effects in Females: Serve to regulate menses Days 1-4: FSH levels increase, stimulating the follicle (egg) to develop and grow Around Day 14: Estrogen reaches a critical level and initiates LH surge. LH mediates ovulation The follicle is now termed a “corpus luteum.”
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Human Menses (Cont’d) If fertilized, CL synthesizes corticogonadotropic hormone HCG in humans Stimulates corpus luteum to keep on secreting progesterone
Background image of page 8
Part II Nervous System Development
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Early Embryo Fertilized Ovum Blastula Post-conception Weeks 1 and 2 Sphere of about 128 cells surrounding a fluid-filled cavity Gastrula Third week post-conception Organizes into three distinct cell layers
Background image of page 10
Gastrulation: The Development of the Ectoderm, Mesoderm and Endoderm The nervous system will develop from the ectoderm—the outermost cell layer.
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Gastrulation: “The Embryo Takes Shape” http://www.pbs.org/wgbh/nova/miracle/program.html
Background image of page 12
Neurulation: Development of the Neural Plate, Neural Crest, and Neural Tube The neural crest rises on both sides And eventually encloses to form the neural tube
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Neural Plate Neural Groove Neural Crest (PNS) Neural Tube (CNS) Thus, Day 21 is very important for the developing CNS. Unfortunately, many women may not even realize they are pregnant.
Background image of page 14
Failure of Neural Tube to Close Anencephaly: Cephalic end of neural tube does not close Missing major portions of the brain, skull and scalp Often born without a forebrain Spina Bifida Caudal neural tube does not close completely Range of severity and incapacitation varies greatly depending on level affected (rostral caudal) Incidence can be decreased by 70% with pre- conception and early pregnancy folic acid supplementation
Background image of page 15

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Neurodevelopmental Processes Proliferation: Cell “birth”; first year; 10-12 Migration: Journey to “job sites” Differentiation: Specialization Myelination: Facilitating communication Synaptogenesis: Forming new synapses
Background image of page 16
Differentiation = Specialization Progenitor cells are “pleuripotent” Can be induced to become any of a variety of adult cell types Stem cell (debate) CNS progenitors may become glial cells or neurons.
Background image of page 17

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Myelination continues for 2 decades!
Background image of page 18
Image of page 19
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}