Search results for: 'tissue cells'

Watch Later 1:09

By: HWC, Views: 6525

During a normal, healthy heartbeat, or what we call a cardiac cycle, the top two chambers of the heart, called the atria, contract simultaneously. Then, as they relax, the bottom two chambers, called the ventricles, contract. This explains what happens during a cardiac cycle, but what it doesn't ...

Watch Later 1:41

Muscle Twitch and Muscle Tension - Motor unit size and force

By: HWC, Views: 6919

• 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...

Watch Later 2:37

Cellular Defects - Osteoblasts, Osteoclasts and Osteocytes

By: HWC, Views: 6323

■ Metabolically active bone-building cells that secrete astroid. ■ Cover surfaces of newly formed bone and respond to growth stimuli ■ Less responsive to growth factors as the body ages. ■ Contribute to hone loss once their reproductive and biosynthetic potential lessens....

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Mechanisms of capillary exchange

By: HWC, Views: 6775

■ 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 2:31

The Pressure Flow Model in a Plant

By: HWC, Views: 6028

The vascular system of plants has two transport tissues, called xylem and phloem. Xylem transports water and minerals, while phloem transports a variety of dissolved substances, including sugars and amino acids, throughout the plant. Water in the xylem always moves up, in the direction from th...

Watch Later 0:40

Erythropoietin (EPO)

By: HWC, Views: 6218

■ Secreted by kidney cells when blood oxygen is low. ■ Targets cells in red bone marrow that will become red blood cells. ■ Promotes increased numbers of mature red blood cells. ■ More mature red blood cells carry more oxygen so blood oxygen level is restored to normal.

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Cleavage and Implantation Animation

By: HWC, Views: 4145

✔ https://HomeworkClinic.com ✔ https://Videos.HomeworkClinic.com ✔ Ask questions here: https://HomeworkClinic.com/Ask Follow us: ▶ Facebook: https://www.facebook.com/HomeworkClinic ▶ Review Us: https://trustpilot.com/review/homeworkclinic.com Fertilization typically takes pl...

Watch Later 2:35

Contraction cycle of a sarcomere

By: HWC, Views: 7181

• A single nervous signal releases Ca2+ ions into the sarcoplasm and initiates the contraction cycle. step 1. ATP hydrolysis • ATP provides the to move myosin molecules back into the energized configuration necessary to perform the power stroke. Step 2. Crossbridge attachment • Myosin...

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Types of antimicrobial substances (interferons & complement protein)

By: HWC, Views: 6735

• Found in blood and interstitial fluids. • Discourage microbial growth. • Include interferon and complement proteins. • Produced and released by virus-infected lymphocytes. • Enter new cells and inhibit viral replication. • Act against a large variety of viruses (non-speci...

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