Search results for: 'lipid envelope'

Watch Later 0:42

By: HWC, Views: 3470

Formation of membrane attack complexes. Complement proteins can activate when they bind to antibodies that are bound to a pathogen. Complement proteins also activate when they bind directly to bacterial surfaces. Cascading reactions yield huge numbers of different types of complement protei...

Watch Later 1:00

HIV replication/ Replication cycle of HIV

By: HWC, Views: 3798

Replication cycle of HIV, one of the retroviruses. The HIV virus is surrounded by a lipid envelope with embedded proteins. A coat of viral proteins surrounds two strands of RNA and the enzymes used during replication. The virus attaches to and enters the host cell. Viral reverse trans...

Watch Later 1:29

Mitosis step-by-step

By: HWC, Views: 4573

During interphase, the chromosomes will be duplicated in preparation for mitosis, which divides the chromosomes, and cytokinesis, which divides the cell's cytoplasm. In early prophase, the duplicated chromosomes begin to condense. Each chromosome consists of two sister chromatids joined at the...

Watch Later 1:39

Molecules, Membrane Permeability and Structure

By: HWC, Views: 6145

Organisms are not isolated system at equilibrium and need to intake nutrients and electrolytes as remove wastes. Similarly Cells within an organism must also exchange compound by passing them through membrane. The permeability of a membrane is the rate of passive diffusion of molecules th...

Watch Later 1:42

Second Messengers in the Inositol-lipid Signaling Pathway

By: HWC, Views: 5880

Extracellular signals produce specific responses in target cells through the action of intracellular second messengers. Here, we focus on three second messengers, IP3, DAG, and Ca2+, all involved in the inositol-lipid signaling pathway. A hormone-receptor signal on the cell surface leads to the a...

Watch Later 1:34

Lipid digestion - mouth, stomach and small intestine

By: HWC, Views: 6749

• Lipid digestion takes place primarily in the small intestine; some occurs in the mouth and stomach. • Lipases are enzymes that break down triglycerides and phospholipids. • Lingual and gastric lipases hydrolyze a small amount of triglycerides. • End products are fatty acids and...

Watch Later 0:31

Simple Diffusion - gases and nonpolar compounds transport

By: HWC, Views: 6980

Gases and some molecules can diffuse through the phospholipid bilayer because they are small or non-polar. Oxygen gas. Carbon dioxide gas. Lipid based hormones. Plasma membranes are selectively permeable: The lipid bilayer is always permeable to small, nonpolar, uncharged molecules ...

Watch Later 2:54

Mechanisms of capillary exchange

By: HWC, Views: 6760

■ The primary role of capillaries is to permit the exchange of nutrients and wastes between the blood and tissue cells (via interstitial fluid). ■ Oxygen and nutrients move from the blood to the cells. ■ Carbon dioxide and other wastes move from the cells to the blood. The three ba...

Watch Later 1:34

Lipid catabolism - lipolysis and beta oxidation and oxidation of fatty acids

By: HWC, Views: 6911

• Digestion hydrolyzes lipids into fatty acids and glycerol. • Fatty acids and glycerol are: • Oxidized to generate ATP. • Used to produce triglycerides that are stored as energy reserves in adipose tissue. • Lipid catabolism begins with lipolysis in which lipids are broken do...

Search Results