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Secondary and tertiary levels of protein structure Animation

By: HWC, Views: 1659

Amino acid sequence dictates a protein's final shape. The presence of certain amino acids favors a pattern of hydrogen bonding that causes part of the polypeptide chain to coil and twist into an alpha helix. The presence of other amino acids enables hydrogen bonding between strand like re...

Wrist Circumduction Animation

By: Administrator, Views: 1240

Circumduction is sometimes described as simply a "circular movement" because circumduction movements of (e.g. the arm and hand) result in the outer edge of the limb (e.g. the fingertips) tracing circles in space. Another way to express this is to say that circumduction is the movement of the dist...

Contraction and Relaxation Animation

By: Administrator, Views: 10654

Muscles are responsible for movement. The types of movement are: - Locomotion, when chemical energy is changed into mechanical energy. - Propulsion of substances through tubes, as in circulation and digestion. - Changes in the sizes of openings, as in the contraction and relaxation of the iris...

Ciliate conjugation Animation

By: HWC, Views: 2126

Protozoan conjugation is an unusual form of sexual reproduction Prospective partners join together, usually at the surface of their oral depressions. The cells undergo cytoplasmic fusion. Meiosis II produces four haploid micronuclei. Now the macronucleus of each cell begins to bre...

Endocrine System Animation

By: Administrator, Views: 1423

Vital function of endocrine system: Production and regulation of chemical substances called hormones. Hormones Chemical transmitters released in small amounts and transported via bloodstream to a target organ or other cells. Transfer information and instructions from one set of cells to anot...

Muscular System Animation

By: Administrator, Views: 10651

Three basic types of muscles: - Skeletal - Smooth - Cardiac Composed of striated or smooth muscle tissue and classified according to their functions and appearance. Skeletal Muscle: - Also known as voluntary or striated muscle. - Controlled by the conscious part of the brain and attach...

Hormones and the menstrual cycle Animation

By: HWC, Views: 4675

Feedback loops to the hypothalamus and pituitary gland from the ovaries during the menstrual cycle Animation for a step-by-step explanation. Production of a releasing hormone (GnRH) by the hypothalamus prods the pituitary's anterior lobe to release FSH and LH. In the ovary, FSH and LH stimula...

Homologous chromosomes during prophase I - Animation

By: HWC, Views: 5619

The chromosomes were duplicated during interphase and the sister chromatids are now in thin threadlike form. Each chromosome becomes zippered to its homologue, so that all four chromatids are closely aligned. The chromosomes are tightly aligned, but we will show them as separate so that y...

Neuron Structure Animation

By: Administrator, Views: 11092

There are several types of neurons, three of which are: Motor neurons, Sensory neurons, Interneurons. The nervous system is usually described as having two interconnected divisions: the central nervous system (CNS) and the peripheral nervous system (PNS). CNS: Includes the brain and spinal...