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Objective 9:
Insulin
structure (9b)
Effect
of insulin on homeostasis (9c/d)
Type
I / II Diabetes (9e)
Play the "Diabetic Dog" Game and test your understanding of insulin action
Objective 12:
Thyroid
hormones (12b)
Objective 13:
Calcium homeostasis
Objective 14:
Other
hormones involved in regulation of blood sugar (15b)
Objective 15:
Adrenal
cortex negative feedback (16e)
Objective 16:
Estrogen
receptor (optional)
Objective 18:
External
versus internal fertilization
Objective 20:
Rat
Dissection Pictures (new!)
Objective 23:
Ovary and placenta
Optional Supplementary Material
"Virgin birth" of hammerhead shark
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Lactation
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| Milk Synthesis. Diagrammatic representation of a mammary gland cell showing
the basic cuboidal shape with typical microvillus border and basal nucleus.
Cytoplasmic organization is characteristic of cells undergoing active protein
synthesis and secretion. The synthetic apparatus consists of many free
ribosomes and an extensive system of rough endoplasmic reticulum. A large
Golgi body is located above the nucleus, and associated with it are some
vacuoles containing fibrillar or particulate material that condenses into
a central core or granule. Toward the apex the granules become progressively
larger and contain more dense protein granules. The vacuoles fuse with
the surface membrane and liberate their contents intact into the lumen.
Fat droplets are found throughout the cell but are largest near the apex.
They protrude into the lumen and appear to pinch off from the cell proper
along with a small bit of cytoplasm. Other cytoplasmic structures include
large mitochondria with closely packed cristae, lysosomes, and a small
number of smooth membranous tubules and vesicles. |
Milk Ejection. Diagram of the mammary alveolus surrounded by a long,
thin myoepithelial cell. Contraction of the myoepithelial cell promotes
a "squeezing" pressure on the gland cells so that milk is forced
to move along the attached duct system. |
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