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How Hemoglobin Picks Up and Delivers Oxygen

By: HWC, Views: 7046

All of the cells in our bodies require oxygen (02) for survival and must release carbon dioxide (CO2) as a waste product. The respiratory and circulatory systems work together as delivery systems for these gases. The lungs exchange these gases between the environment and the bloodstream. The bloo...

Second Messengers in the Inositol-lipid Signaling Pathway

By: HWC, Views: 7014

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...

Cardiac Cycle (Part 2 of 4)

By: Administrator, Views: 10792

Prior to atrial systole, blood has been flowing passively from the atrium into the ventricle through the open AV valve. During atrial systole the atrium contracts and tops off the volume in the ventricle with only a small amount of blood. Atrial contraction is complete before the ventricle begins...

Primary and secondary response to infection

By: HWC, Views: 7489

• Pathogens enter the body by penetrating the non-specific barriers in the skin and mucus membranes. • Pathogens first encounter macrophages and natural killer cells that carry out phagocytosis and cytolysis respectively. • A pathogen's first encounter with the immune system can promo...

Gas exchange - partial pressure, locations, external and internal respiration

By: HWC, Views: 7900

▪ In a mixture, each individual gas exerts a pressure that is proportional to the concentration of that gas within the mixture. • This part of the total pressure is called a "partial pressure". • A gas moves along the part of the pressure gradient determined by its own concentration. ...

Upper Limb Arteries Animation

By: Administrator, Views: 700

Arteries A branching system of vessels that transports blood away from the heart to all body parts. All arteries have a pulse, reflecting the rhythmical beating of the heart. Arteries Certain points are commonly used to check rate, rhythm, and condition of the arterial wall. Most commonly ...

Premenstrual Syndrome

By: Administrator, Views: 10947

Premenstrual syndrome (PMS) refers to physical and emotional symptoms that occur in the one to two weeks before a woman's period. Symptoms often vary between women and resolve around the start of bleeding. Common symptoms include acne, tender breasts, bloating, feeling tired, irritability, and mo...

Baroreceptor Reflex

By: HWC, Views: 7086

Baroreceptors located In the carotid sinus and the arch of the aorta respond to increases in blood pressure. Increased blood pressure stretches the carotid arteries and aorta causing the baroreceptors to increase their basal rate of action potential generation. Action potentials are conduct...

Lower Limb Arteries Animation

By: Administrator, Views: 10874

Arteries A branching system of vessels that transports blood away from the heart to all body parts. All arteries have a pulse, reflecting the rhythmical beating of the heart. Arteries Certain points are commonly used to check rate, rhythm, and condition of the arterial wall. Most commonly ...