Homeostasis pt 2

Hormone secreting gland cell- hormone - blood vessel,

target cells in one or more distant places in the body

Neuron, electrical signal, neurotransmitter,

Neuron or effectors cell in close proximity to site of neurotransmitter release

Local cell, paracrine substance,

target cells in close proximity to site of release of paracrine substance

Local cell, autocrine substance

autocrine substance acts on same cell that secreted the substance

A given chemical messenger can fit into more than one category, true or false

True

Example of a chemical messenger that fits into more than one category

Steroid hormone, cortisol affects the very cells which it is made, nearby cells that produce other hormones and many distant targets, including muscles and the liver

2 important types of chemical communication between cells that do not require secretion of a chemical messenger:

Gap junctions and Juxtacrine signaling (contact dependent)

Gap junctions are - - connecting the - between two cells allowing molecules to move from

Physical linkages connecting the cytosol between two cells, allowing molecules to move from 1 cell to an adjacent cell without entering the extracellular fluid

Juxtacrine signaling

chemical messenger not released from the cell producing it, it's located in the membrane of that cell. When cell encounters another cell capable of responding to the message, the two cells link up via membrane bound messengers

Adaptation

Adaptations denotes a characteristic that favors survival in specific environments, adaptation is permanent

Acclimization refers to

Improved functioning of an already existing homeostatic system. Sometimes this is due to prolonged exposure to an environmental change. This is temporary.

Many body functions are associated with

rhythmical changes

The suprachiasmatic nucleus in the -, regulates the

in hypothalamus; regulates the circadian rhythm

Most common type of biological rhythm is the - - which cycles once ever

Circadian rhythm, 24hrs

Waking/sleeping, body temperature, hormone concentrations in the blood, excretion of ions into urine and many other functions undergo

Circadian variation

Biological rhythms add an - component to - - systems

Anticipatory, homeostatic control

Seeing a lemon and starting to salivate is an example of

Biological rhythms adding an anticipatory component to control systems

Negative feedback homeostatic responses are

Control responses

Corrective responses are initiated after the - - of the individual has been disturbed

Steady state

Jet lags an example of

Corrective response

Biological rhythms enable homeostatic mechanisms to be utilized immediately and automatically by activating them at times when a change is likely to occur before it does, like when you try to sleep in after waking up at 6am everyday for a year. How does it do this knowing you're about to wake up?

it releases cortisol and increases body temperature.