Search results for: 'Primary consumers'

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By: HWC, Views: 6208

All of these relationships between different species are founded on one thing: energy. Organisms get food in order to get energy, which is used by the organism for growth, maintaining health, and reproduction. We can classify the members of a community according to how they obtain food. Produc...

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Primary and secondary response to infection

By: HWC, Views: 6382

• 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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Hormonal regulation of pregnancy - weeks 2 through 38

By: HWC, Views: 7115

Weeks 2 through 16 • During the first few months of pregnancy, estrogen and progesterone are secreted primarily by the corpus luteum. • These hormones act to maintain nutritional support for the embryo and fetus. • hCG production increases, peaking at 8 weeks. • hCG triggers the c...

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Phases of the ovarian cycle

By: HWC, Views: 7019

• The ovarian cycle is a monthly sequence of events, consisting of three phases: • Preovulatory • Ovulatory • Post ovulatory Preovulatory phase • prior to ovulation: Primary follicles develop into secondary follicles. • Follicular cells surrounding the primary oocyte In...

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Lactation and Breast Feeding

By: HWC, Views: 7471

Regulation of lactation - breast preparation • Pregnancy hormones trigger breast changes to prepare for feeding the new baby. • The amount of the hormone prolactin, essential to the initiation of lactation, increases steadily throughout pregnancy. • However, high levels of both estroge...

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Digestive chemicals - water, gastric acid, bile & bicarbonate

By: HWC, Views: 6352

• Water is the most abundant molecule in ingested fluids. • Water plays a primary role in hydrolytic digestive reactions. • Helps liquefy and transport digestive foodstuffs down the tract. • Transports secretions from accessory digestive organs to gastrointestinal tract. • Aids ...

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Egg and Sperm Formations in Animals Animation

By: HWC, Views: 424

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. ...

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Digestive System Animation

By: Administrator, Views: 9896

Digestive system contains both primary and accessory organs for the conversion of food and fluids into a semiliquid that can be absorbed for the body to use. Three main functions: - Digestion - Absorption - Elimination With aging: - Digestive system becomes less motile. - Glandular sec...

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The primary factors that affect circulation - MABP, CO and SVR

By: HWC, Views: 6934

Introduction Blood flow is determined by the relative intensities of factors that drive and resist moving blood. • Cardiac output (CO) equals the mean arterial blood pressure (MABP, a driving force) divided by systemic vascular resistance (SVR, a resisting force). • Hormones and the cen...

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