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Origin of organelles Animation

By: HWC, Views: 1365

Possible origins of the nucleus and other organelles. Some prokaryotic cells have infoldings of their plasma membrane. These infoldings may have served as channels from the cytoplasm to the cell surface. These membranous folds may have evolved into the endoplasmic reticulum and the nuclear e...

Gas exchange - driving force

By: HWC, Views: 7793

• The respiratory system is responsible for the movement of gases involved in cellular metabolism. • Oxygen is used up and carbon dioxide is generated during the aerobic breakdown of glucose and other fuel molecules in order to produce ATP. • Three important continuous physiological pro...

Membrane transport proteins - pores, gated channels and pumps

By: HWC, Views: 7847

• a Three different types of membrane ion transport proteins are required to produce and carry electrical signals: • Pores • Gated channels • Na+/ K+ pump • Pores are always open and allow the diffusion of Na+ and K+ ions across the membrane, down their concentration gradients...

ADH and the arterioles, kidneys, sweat glands and the Atrial natriuretic peptide (ANP)

By: HWC, Views: 7820

• ADH is also known as vasopressin. • Produced by hypothalmus and secreted by neurosecretory cells in posterior pituitary gland. • Responds to high blood osmotic pressure representing low amounts of water in the blood. • Binds to smooth muscle cells in walls of arterioles, stimulate...

Vascular tissues in a corn stem and a buttercup root

By: HWC, Views: 2221

Vascular tissues in a corn stem and a buttercup root. The cells that make up each tissue. Xylem conducts water and dissolved ions. It also helps mechanically support a plant. The cells, called vessel members and tracheids, are dead at maturity. Their lignified walls interconnect and serve as p...

Five phases of cardiac cycle & Atrial contraction

By: HWC, Views: 7759

1. Atrial contraction (atrial systole). 2. Isovolumetric (ventricular) contraction. 3. Ventricular ejection. 4. Isovolumetric (ventricular) relaxation. 5. Passive ventricular filling. Beginning of cardiac cycle • Prior to atrial contraction: • Atria and ventricles are relaxed....

Neurotransmission at chemical synapses & Excitory and inhibitory potentials

By: HWC, Views: 7651

• A series of events occur at chemical synapses in order to communicate with the adjacent cell. • The action potential arrives at the presynaptic membrane. • The depolarization phase of the action potential opens voltage gated Ca+ channels. • increased inflow of Ca+' into the cyto...

Types of Shock (Part 2 of 2)

By: Administrator, Views: 10360

Shock is a life-threatening condition in which delivery of oxygen to the organs is low, causing organ damage and sometimes death. Blood pressure is usually low.

Coronary Heart Disease Animation

By: Administrator, Views: 10995

Arteriosclerotic heart disease occurs when arterial vessels are marked by thickening, hardening, and loss of elasticity in arterial walls. Course of cardiovascular disease accelerates due to: Reduced blood flow Rlevated blood lipids Defective endothelial repair