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Negative Feedback Regulation of Blood Pressure

By: HWC, Views: 7719

stimulus • Blood pressure determines the flow of blood to and from capillaries. • Low blood pressure results in reduced blood flow. • High blood pressure can cause blood vessels to break. Baroreceptors • The aortic arch carries blood to the body. • The common carotids ca...

Muscle Twitch and Muscle Tension - Motor unit size and force

By: HWC, Views: 7964

• A motor unit is a group of muscle cells controlled by a single neuron. • A stimulus of sufficient intensity will cause all the cells in the motor unit to contract. • A single contraction, caused by a single action potential, is called a muscle twitch. • Latent period: A brief per...

Primary and secondary response to infection

By: HWC, Views: 7470

• 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...

Control of ventilation rate by other brain centers (posts, hypothalamus & cerebral cortex)

By: HWC, Views: 7667

Forced ventilation: • The inspiratory area stimulates accessory inspiratory muscles. • Inspiration is more forceful. • Inspiratory area activates expiratory area, which sends impulses to the expiratory muscles (internal intercostals and abdominal muscles). • Expiration muscles c...

Methods of carbon dioxide transport - carbaminohemoglobin and bicarbonate ions

By: HWC, Views: 7775

• Carbon dioxide is transported three ways: • As bicarbonate ions in the plasma. • Bound to hemoglobin. • As a dissolved gas in the plasma. • A small percent of carbon dioxide is transported as a dissolved gas. • Some of the carbon dioxide is bound to hemoglobin, in the fo...

Antidiuretic hormone (vasoconstriction, water reabsorption & sweat inhibition)

By: HWC, Views: 7600

• Dehydration, blood loss, and low amounts of water in the blood can cause blood volume and pressure to decrease. • Neurosecretoxy cells in the posterior pituitary release antidiuretic hormone(ADH). • ADH binds to smooth muscle cells in blood vessel walls, stimulating them to vasoconstr...

Acids and bases - definition

By: HWC, Views: 7617

Acids and bases are found all around your house. For example, if you open your pantry or refrigerator, you might see a lot of acids. Fruit juice, soda pop, vinegar, and milk are all examples of acids. The word acid actually comes from a Latin term meaning ''sour.'' Many materials, like sugar for ...

Ventilation - phases and driving forces

By: HWC, Views: 7790

Respiration is the exchange of gases between the atmosphere, blood, and cells The combination of 3 processes is required for respiration to occur Ventilation (breathing) External (pulmonary) respiration Internal (tissue) respiration The cardiovascular system assists the respiratory system b...

Egg and Sperm Formations in Animals Animation

By: HWC, Views: 1966

Inside the ovaries of a female animal are diploid germ cells called oogonia. An oogonium grows to become a primary oocyte. This large cell is still diploid. Meiosis I followed by unequal cytoplasmic division produces one large secondary oocyte and a smaller polar body. Both are haploid. ...