Search results for: 'Helper T cell proliferation and differentiation'

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By: HWC, Views: 7711

• The endocrine system maintains many body conditions within normal limits with feedback loops. Each endocrine feedback loop maintains homeostasis using the following components: • Stimulus - a change in a body condition. • Production cell - an endocrine cell that produces a hormone aft...

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Embryonic development - week 1 and 2

By: HWC, Views: 7688

The first through eighth weeks after fertilization are called the embryonic. Week 1 • Within a day, the zygote begins mitotic cell division (cleavage) forming blastomeres. By the 4th day, the blastomeres have formed a solid ball called a morula. • The morula enters uterine cavity ar...

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Uterine (menstrual) cycle - phases

By: HWC, Views: 7713

• The uterus goes through a cyclical developmental pattern to be ready for implantation and support of an embryo. • The uterine, or menstrual, cycle is under the control of ovarian horrnones. • The uterine cycle also has three phases: • Menstrual phase • Proliferative phase �...

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Primary and secondary response to infection

By: HWC, Views: 7471

• 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...

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Fertilization Animation

By: Administrator, Views: 429

At conception, the gender and other biologic traits of the new individual are determined. The zygote is genetically complete and immediately begins to divide, forming a solid mass of cells called a morula. When the developing embryo (stage of development between weeks 2 and 8) reaches the ute...

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Chemical Synapse Animation

By: HWC, Views: 5095

A neuromuscular junction is a chemical synapse between the axon endings of a motor neuron and a muscle cell. A narrow synaptic cleft separates the presynaptic cell (the motor neuron) from the postsynaptic cell (the muscle cell). The presynaptic cell contains vesicles filled with neurotransmitt...

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Osmosis - Isotonic, Hypotonic, and Hypertonic Solutions

By: HWC, Views: 7825

Isotonic: Equal Water moves in and out of the cell at an equal rate. The cell remains unchanged. Hypotonic: "hypo" hippo Water moves into the cell, making it swell and get fat (like a hippo). Eventually the cell can rupture and burst (aka lyse). Hypertonic: "like a raisin" Water leaves...

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Embryonic development - Week 3

By: HWC, Views: 7752

Week 3 (gastrulation) • Three primary germ layers are formed which provide cells for organ formation in the following months. • These germ cell layers are formed by a process known as gastrulation, which involves rearranging epiblast cells. • As cells from the epiblast migrate, a fain...

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Sickle Cell Anemia

By: Administrator, Views: 10770

The clinical manifestations of sickle cell anemia result from pathologic changes to structures and systems throughout the body.

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