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Synaptic Transmission

> synapse: spaces between neurons, or between neurons and effectors > vesicles containing chemical neurotransmitters are located at the end of neuron axons Electrical Signals: > electrical impulses moving along the axon stimulate the release of neurotransmitters Chemical Signals: > neurotransmitters are released from the presynaptic neuron and diffuse across the synaptic cleft > neurotransmitters…

The Nervous System Anatomy and Function

The nervous system is an elaborate communication system that functions to regulate the actions of your body to maintain the internal environment within safe limits Nerve Cells: Glial cells – non-neuronal cells that provide support and nutrition, maintain homeostasis, form myelin, and participate in signal transmission in the nervous system. Functions: – surround neurons and…

Thermoregulation

Thermoregulation is the maintenance of body temperature within a range that enables cells to function efficiently. Mammals, including humans, are endotherms, able to maintain a constant body temperature regardless of our surroundings. The hypothalamus acts as your body’s “thermostat”, detecting changes in body temperature and sending out messages to help restore the normal body temperature.…

Energy Flow in Living Systems

Living organisms must continually capture/acquire, store, and use energy to carry out the functions of life. Capturing/acquiring, storing and using energy are accomplished through cellular chemical processes. Cells are chemical machines that obey fundamental chemical and physical laws of nature. The sum of a cells chemical reactions is called metabolism. Energy Energy is the ability…

Shapes of Molecules

The shape of a molecule determines many of its properties; For example: C4H10 is the formula for 2 separate molecules n-butane and isobutene Melting Point    -138°C                   -159°C Boiling Point     -0.5°C                    -12°C Enzymes—shape compatible with those molecules whose reactions they promote i.e.  the enzyme sucrase breaks down the sugar molecule sucrose The shape of a…

Rate Laws and Order of Reaction

Chemical reactions only take place when there are collisions between reactants Depends on: Number of collisions per unit time Fraction of collisions which are successful There is a relationship/pattern between reaction rate and the factors that affect it This pattern can only be determined empirically (through experimentation) Rate Law Empirical evidence supports that the reaction…