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Type of Cell Junctions - Desmosome, Hemidesmosomes and Gap Junctions

By: HWC, Views: 8072

Cell Junctions: Cell junctions are found in some multi-cellular organisms. They exist of complexes and are found between cells and between cells and other structures. The junctions provide a way for cells to connect and exchange signals. What are tight junctions, desmosomes, and gap junctions...

Simple and Double Sugar

By: HWC, Views: 7485

Here are the molecular structures of three simple sugars: glucose, ribose, and fructose. Look at these simple sugars and identify what characteristics they all share. As you can see, all of the carbohydrates have carbon, hydrogen, and oxygen in a ratio of 1:2:1 and there is always a double bo...

Definition of heart rate

By: HWC, Views: 7856

• Heart rate is determined by the rate of depolarizations of the sinoatrial (SA) node. • Cardiac output is directly proportional to heart rate, the greater the heart rate the greater the cardiac output. • Changes in heart rate are associated with exercise, stress or injury. Nervous ...

Oxygen transport - methods and oxyhemoglobin

By: HWC, Views: 7535

• The blood is the medium used for gas transport throughout the body. • Oxygen is only available in the lungs. Because the partial pressure of oxygen is higher in the alveoli than in the blood, oxygen diffuses into the blood and is transported to systemic cells. • At the tissues the par...

Blood Flow through the Human Heart

By: HWC, Views: 7487

The heart is the pump of the human circulatory system. The left side of the heart has two connected chambers, the left atrium and the left ventricle. The right side of the heart also has two connected chambers, the right atrium and the right ventricle. These two sides, or pumps, of the heart are ...

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...

Autonomic Nervous System Animation

By: Administrator, Views: 10990

Parasympathetic Division Works to conserve energy and innervate the digestive system. When activated, it: stimulates the salivary and digestive glands. decreases the metabolic rate. slows the heart rate. reduces blood pressure. promotes the passage of material through the intestines along...

Ventilation - phases and driving forces

By: HWC, Views: 7789

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...

Structures that affect circulation - kidneys and blood volume and skeletal muscle pumping

By: HWC, Views: 8287

• Kidneys regulate blood volume and blood osmolarity via salt and water reabsorption. • Increased reabsorption increases blood volume and venous return (and CO). • Decreased reabsorption Increases urine production, which decreases blood volume and venous return (and CO). • Systemi...