Search results for: 'human-lungfish'

Watch Later 2:55

How proteins function? How do proteins work?

By: HWC, Views: 7409

How proteins function is really about how proteins "do work" in cells. How do proteins work? Let's start thinking about protein function by looking at something important to you: your hair. Keratin is a structural protein that is composed of 2 intertwined or helical strands. Keratin is also f...

Watch Later 1:30

Male Reproductive System - The gonadotropin releasing hormone

By: HWC, Views: 8482

• Hormonal mechanisms that influence male reproductive function involve endocrine tissues contained in the: • Hypothalamus of the brain. • Anterior pituitary. • Testes. • In the hypothalamus, certain neurosecretory cells secrete gonadotropin- releasing hormone (GnRH). • GnRH ...

Watch Later 2:01

Phases of the Female Reproductive Cycle - Hormonal regulation

By: HWC, Views: 8190

FSH, LH and estrogen • FSH travels through the bloodstream from the anterior pituitary to the ovaries. • FSH promotes follicular growth. Increased follicular growth promotes estrogen production. • Small increases in blood estrogen levels inhibit the release of FSH and LH into the bl...

Watch Later 0:40

Stomach peristalsis - Movement of Food Through the Small Intestine

By: HWC, Views: 7768

Peristalsis is a series of wave-like muscle contractions that moves food to different processing stations in the digestive tract. The process of peristalsis begins in the esophagus when a bolus of food is swallowed. The strong wave-like motions of the smooth muscle in the esophagus carry the food...

Watch Later 2:31

Uterine (menstrual) cycle - phases

By: HWC, Views: 7728

• The uterus goes through a cyclical developmental pattern to be ready for implantation and support of an embryo. • The uterine, or menstrual, cycle is under the control of ovarian horrnones. • The uterine cycle also has three phases: • Menstrual phase • Proliferative phase �...

Watch Later 2:14

Ionic bonds - role of ions in the body

By: HWC, Views: 7937

Ions • Atoms fill up the outer orbital by transferring electrons from one atom to another. • Atoms now bear a charge and are called ions. • Sodium ion, losing an electron, has a +1 charge. • Chlorine ion, gaining an electron, has a -1 charge. Formation • An ionic bond is t...

Watch Later 0:23

Cerebral Cortex Animation

By: Administrator, Views: 11081

The cerebral cortex (plural cortices), also known as the cerebral mantle, is the outer layer of neural tissue of the cerebrum of the brain, in humans and other mammals. It is separated into two cortices, by the longitudinal fissure that divides the cerebrum into the left and right cerebral hemisp...

Watch Later 1:51

Lactation and Breast Feeding

By: HWC, Views: 8550

Regulation of lactation - breast preparation • Pregnancy hormones trigger breast changes to prepare for feeding the new baby. • The amount of the hormone prolactin, essential to the initiation of lactation, increases steadily throughout pregnancy. • However, high levels of both estroge...

Watch Later 2:19

Male Reproductive System - Testosterone

By: HWC, Views: 8346

• Under the influence of FSH and testosterone, Sertoli cells produce androgen-binding protein (ABP) that binds to testosterone and maintains high levels of the hormone near spermatogenic cells. • Testosterone stimulates the final stages of spermatogenesis. • In addition, testosterone is...

Search Results