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Polymerase chain reaction PCR - Animation

By: HWC, Views: 481

Polymerase chain reaction (PCR) is a method that amplifies fragments of DNA. The purpose of PCR is to create copies of a specific region of DNA. To use this technique, researchers must know the base sequences at either end of the region of interest. They use this information to create...

Generalized life cycles for plants and animals Animation

By: HWC, Views: 477

But the life cycles of plants and animals differ in their details. In animals, a multicelled diploid stage gives rise to single-celled haploid gametes, the eggs and sperm. These gametes combine at fertilization to form a diploid zygote, which grows and develops into a new multicelled animal...

Female Reproductive System - Hormonal regulation (GnRH) الجهاز التناسلي للأنثى - التنظيم الهرموني

By: HWC, Views: 7087

• There is a complex interaction between the anterior pituitary gland, the hypothalamus, the ovaries and the uterus that leads to the monthly changes that women experience during their monthly reproductive cycle. • Two monthly cycles constitute these changes: • Ovarian cycle. • Uter...

Four Giant Convection Cells oF Earth

By: HWC, Views: 5964

Earth Has Four Giant Convection Cells Earth's climates range from dry and cold at the poles to wet and warm at the equator. These climates are dictated largely by the amount of solar radiation that a region receives. Solar radiation warms the Earth and the surrounding air, setting up convection c...

Structures that affect circulation - heart and systolic/diastolic BP

By: HWC, Views: 6595

• Heart generates blood pressure. • Arterioles produce resistance thereby regulating blood flow to tissues. • Veins store blood; kidneys regulate blood volume; both affect venous return and cardiac output. ■ Contractions of the ventricles determine blood pressure, which drives th...

Fractures Animation

By: Administrator, Views: 9629

Types of fractures: - Colles' - Pott's - Compression - Vertebral compression - Epiphyseal - Stress - Hip Closed, or simple–A completely internal break that does not involve a break in the skin (x-ray of the tibia and fibula). Note the break in the fibula (smaller bone). Open, or co...

Basic rhythm - control centers in medulla oblongata, spirograph and normal tidal cycle

By: HWC, Views: 6579

• Normal ventilation is rhythmic and involves continuous cycles of inspiration and expiration. • Various regions of the brain closely regulate this rhythmic pattern of ventilation. • The rhythmicity area in the medulla regulates the basic rhythm of ventilation. • The medullary rhy...

Contraction cycle of a sarcomere

By: HWC, Views: 7169

• 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...

The Hypothalamus: The Body's Thermostat (Human Thermostat)

By: HWC, Views: 5895

Normal body function requires a relatively constant body temperature, which is regulated by the body's thermostat, a region of the brain called the hypothalamus. The hypothalamus generates a temperature set point for the body and appears to be the major site for the integration of temperature inf...