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Negative Feedback Regulation of Blood Pressure

By: HWC, Views: 7734

stimulus • Blood pressure determines the flow of blood to and from capillaries. • Low blood pressure results in reduced blood flow. • High blood pressure can cause blood vessels to break. Baroreceptors • The aortic arch carries blood to the body. • The common carotids ca...

Regulation of GFR: autoregulation via tubuloglomerular feedback, neural & hormonal regulation

By: HWC, Views: 8914

• When blood pressure is above normal, rapid filtrate flow reduces ion retention so filtrate in tubule has more Na+, C1-, and water. • It is believed that vasoconstricting chemicals from the juxtaglomerular cells are released when the macula densa cells detect higher water and ion levels in ...

Fetal development - Weeks 9 to 38

By: HWC, Views: 7875

Weeks 9-12 • Fetal development during the third month includes: • A large head, about 1/2 the length of the fetus. • Visible eyes and ears. • A detectable heartbeat. • Kidneys that form urine. • Gender identification. • Weak, undetectable body movements. • By the e...

Brain Anatomy Animation (Part 2 of 2)

By: Administrator, Views: 11973

Its nervous tissue consists of millions of nerve cells and fibers. It is the largest mass of nervous tissue in the body. The brain is enclosed by three membranes known collectively as the meninges: dura mater arachnoid pia mater The major structures are the: cerebrum cerebellum dienc...

Homeostasis (range of body conditions, normal limits, mild stresses & severe stresses)

By: HWC, Views: 7702

Homeostasis: • Provides relative stability of the internal environment. • Results from constant adjustments. • Regulated by regulatory processes. • Requires system interplay. • Normal limits. • Temporary stresses. • Disruptions requiring medical intervention. • D...

Labor and Childbirth - The Three Stages of Labor: Dilation, Expulsion & Placental مراحل الولادة

By: HWC, Views: 8181

Regulation of labor and birth - effects of estrogen and oxytocin on onset of labor • Just prior to birth, high placental corticotropin-releasing hormone levels stimulate the production of more estrogen. • High estrogen levels overcome the inhibitory effects of progesterone on uterine sm...

Proteins Defined, Hierarchy & Composition of Cells

By: HWC, Views: 7212

Proteins are long chains of amino acids linked together by peptide bonds. Together with the other three biological macromolecules—carbohydrates, lipids, and nucleic acids—proteins are the building blocks of cells. Proteins are the most complex and abundant biological macromolecules in cel...

Hormonal regulation of pregnancy - weeks 2 through 38

By: HWC, Views: 8165

Weeks 2 through 16 • During the first few months of pregnancy, estrogen and progesterone are secreted primarily by the corpus luteum. • These hormones act to maintain nutritional support for the embryo and fetus. • hCG production increases, peaking at 8 weeks. • hCG triggers the c...

Photosynthesis and Van Helmont Experiment

By: HWC, Views: 6997

All energy on Earth comes from a star, the Sun. Light must travel 160 million kilometers to reach Earth where plants capture this light energy and convert it to chemical energy in the form of sugars. This biochemical process is called PHOTOSYNTHESIS. The summary equation for photosynthesis is ...