Search results for: 'sieve-tube'

Watch Later 1:29

By: HWC, Views: 6989

• Fertilization is the process by which the two gametes from the parents fuse their genetic material to form a new individual (zygote). • Fertilization requires that sperm cells swimming through the uterine tube contact a secondary oocyte. • Once sperm penetrate the secondary oocyte's ...

Watch Later 2:10

Power Supply Polyacrylamide Gel Protein Sample

By: HWC, Views: 5997

SDS-polyacrylamide gel electrophoresis is a powerful tool, which resolves proteins according to their molecular weights. Because proteins differ in size, shape, and charge, a protein sample is first denatured with the anionic detergent SDS. When the sample is heated, the SDS molecules bind to ...

Watch Later 1:42

Atrial natriuretic peptide (vasodilation) & Aldosterone

By: HWC, Views: 6313

• Certain situations will cause the body's stress level to rise. • increased blood pressure will stretch the atria of the heart, stimulating the secretion of atria natriuretic peptide (MP). • ANP causes muscle cells in blood vessels to relax. • Blood pressure is lowered as a result ...

Watch Later 0:28

Sperm Formation Animation

By: Administrator, Views: 350

A man’s reproductive system is specifically designed to produce, store, and transport sperm. Unlike the female genitalia, the male reproductive organs are on both the interior and the exterior of the pelvic cavity. They include: the testes (testicles) the duct system: epididymis and vas def...

Watch Later 1:20

Miller's reaction chamber experiment Animation

By: HWC, Views: 248

A simple diagram of Stanley Miller and Harold Urey's experimental apparatus. The lower portion of the apparatus was filled with water. The upper portion was filled with a mixture of gases that simulated the earth's early atmosphere. Examples are methane, ammonia, hydrogen and carbon dioxide. ...

Watch Later 2:50

Neural regulation of mechanical digestion- CNS voluntary, ANS & ENS controlled involuntary movements

By: HWC, Views: 6553

• The gastrointestinal [GI] tract is basically a muscular tube that contains and processes food as it moves from the mouth to the anus. • Mechanical digestive functions consist of both voluntary and involuntary muscle contractions and relaxation including: • Chewing and swallowing food....

Watch Later 2:46

Predator- prey competition and symbiosis

By: HWC, Views: 6453

Predator-prey relationships occur when one species, the predator, kills and eats an organism of another species, the prey. This graph shows the cyclical nature of predator-prey relationships, in this case among populations of Canada lynx and snowshoe rabbits. If predation is without some li...

Watch Later 0:53

Labor and Delivery - Infant Cord Apgar

By: Administrator, Views: 303

As soon as your baby is born, a delivery nurse will set one timer for one minute and another for five minutes. When each of these time periods is up, a nurse or physician will give your baby her first "tests," called Apgars. This scoring system (named after its creator, Virginia Apgar) helps t...

Watch Later 2:51

hGH, Thyroid hormones & Aldosterone

By: HWC, Views: 6682

Glycogenolysis and lipolysis • Stressors stimulate production of a hypothalamic releasing hormone (GHRH). • The releasing hormone stimulates somatotroph cells of anterior pituitary to secrete human growth hormone. • Human growth hormone targets liver cells and fat cells. hGH (glycog...

Search Results