What is a tissue?
Grouping of similar cells
What is an organ?
A structure with a particular function, made up of 1 or more tissue types
What are the main tissue types? What are their functions?
Epithelial—secretion/barrier
Muscle—force/movement
Nervous—information transport/processing
Connective—structure/support
What is homeostasis?
When the body maintains internal equilibrium
What is the set point?
The reference value for the variable you are trying to regulate.
What is the comparator?
It recognizes when we move to and from a set point
What are regulatory systems and what do they do?
They obtain, integrate and process information and issue commands to effectors. Muscles and glands are considered effectors.
What is a negative feedback system?
Information is used to counteract the influence that created an error signal. A thermostat for example.
What is a positive feedback system?
It amplifies a response and increases deviation from a set point. Ex—breastfeeding.
What is an example of a positive feedback mechanism and why?
Breastfeeding because nerve cells in your nipple signal the brain to release oxytocin, oxytocin causes muscle in breast to contract, breast milk is ejected out of your milk ducts, your baby suckles, and repeat.
Explain the process of eating too many gummy bears in relation to glucose.
The level of glucose in your body increases greatly which then causes the Beta cells in your pancreas to release insulin into the bloodstream and insulin receptors in the liver receive the signal and take up glucose converting it into glucagon for storage.
What do temperatures of hotter than 45°C (113°F) and colder than 0°C (32°F) do to the body?
In those hotter temperatures, protein degradation occurs and in the colder temperatures, cellular dehydration occurs.
What are heat shock proteins (HSP)?
They are proteins that protect the cell from losing integrity by helping them retain protein folding and helping them renature in the face of cell stress/heat.
What are isozymes?
They are enzymes that have the same function but may have different tolerances.
What are isoforms?
Non-enzymes that have the same function.
What does Q10 describe?
It describes how sensitive a metabolic or physiological process is to temperature change.
Metabolism vs. Temperature rise
Metabolism which is a chemical process that helps a body sustain life is faster as temperature rises.
What are homeotherms?
They maintain constant body temperature.
What are poikilotherms?
They have fluctuating body temperature.
What are endotherms?
They change metabolic rate to regulate temperature.
What are ectotherms?
They depend on environment to regulate temperature.
What are the avenues of heat exchange used by ectotherms and endotherms?
Radiation—heat transfer via infrared radiation from warmer to cooler areas
Conduction—heat transfer between objects in direct contact
Convection—heat transfer with a surrounding medium such as air or water
Evaporation—heat transfer as water converts to gas (ex. sweating)
What is vasoconstriction?
The constriction of blood vessels that service the skin to reduce heat loss. The goal is to keep you warmer!
What is vasodilation?
Increased blood flow to the skin increases heat loss and lowers body temperature. This is to make yourself cool down!