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Chemical Changes

By: HWC, Views: 7119

Observe the burning logs of wood. The logs burn to emit heat, light and carbon dioxide. What is left behind is ash. This residue is a new substance with a different molecular structure than the original wood. Similarly when baking the dough into bread, it becomes fluffy and light. There is a ch...

Types of synapses - electrical & chemical

By: HWC, Views: 7818

• Neurons communicate with one another or effector cells via synapses that allow information to be filtered and integrated. • The two types of synapses are: • electrical • chemical. • Electrical synapses, also known as gap junctions, contain many ion channels (connexons) conne...

Chemical Messengers Animation

By: Administrator, Views: 11295

Three types of chemical messengers.

Endocrine System Animation

By: Administrator, Views: 1421

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...

Digestive chemicals - types & enzymes

By: HWC, Views: 7706

• Chemical digestion breaks down food as it moves through the digestive tract. • Using enzymes and other digestive chemicals, the process reduces food particles into nutrient molecules that can be absorbed. • Most chemical digestion is done by the actions of digestive enzymes. • O...

Oxygen transport: association and dissociation & Factors that affect hemoglobin's saturation with O2

By: HWC, Views: 7665

• The production of oxyhemoglobin can be illustrated through the following reaction: 02 + Hb-H --) Hb-02 + H+ • This equation represents the binding of oxygen to the iron ions in heme groups in hemoglobin molecules. • Oxygen binding or loading occurs at the lungs • The dissociatio...

Neurotransmission at chemical synapses & Excitory and inhibitory potentials

By: HWC, Views: 7645

• A series of events occur at chemical synapses in order to communicate with the adjacent cell. • The action potential arrives at the presynaptic membrane. • The depolarization phase of the action potential opens voltage gated Ca+ channels. • increased inflow of Ca+' into the cyto...

Anatomy and Chemical Makeup of a Single Hair (Animation)

By: HWC, Views: 5923

The hair's outer cuticle surrounds hair cells filled with tough keratin macrofibrils. Each macrofibril consists of smaller microfibrils. A microfibril is made up of three keratin polypeptide chains. The chains are linked together by disulfide bonds. A hair consists of keratin chains held...

Chemical Synapse Animation

By: HWC, Views: 5092

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...