Module 3

anatomy

anatomy

the study of body structures (form)

physiology

the study of body function

nervous tissue

internal communication- brain, spinal cord, and nerves

muscle tissue

contracts to cause movement- muscles attached to bones (skeletal), muscles of the heart (cardiac), muscles of walls of hollow organisms (smooth)

epithelial tissue

forms boundaries between different environments, protects, secretes, absorbs, filters- skin surface, lining of GI tract organs and other hollow organs

connective tissue

supports, protects, binds other tissues together- bones and cartilage, tendons and ligaments, fat and other soft padding tissue, blood

nervous system

electrical and chemical signals called neurotransmitters, travel through neurons

endocrine system

chemical signals called hormones, travel though blood

homeostasis

set points of internal temperatures, pressures, and other conditions to stay alive

negative feedback

returns us to homeostasis, stops, reduces, or dampens the stimulus

positive feedback

moves us away from homeostasis, activates, increases , or encourages the stimulus

circadian rhythm

regular daily fluctuations in our bodies, mostly maintained in absence of external cues

acclimatization

organisms change according to environment

endothermic

warmed by internal mechanisms

exothermic

rely on external sources for heat, “cold-blooded” is misleading

radiation

emission of heat energy

evaporation

removal of water also removes heat

convection

transfer of heat from movement of air or liquid (why wind makes you feel colder)

conduction

direct transfer of heat between objects in contact with each other

countercurrent exchange systems

reduce heat loss in limbs and other body parts with high surface area

metabolism

all of the chemical reactions occurring in an organism

metabolic rate

the sum of all the energy used in a period of time

basal metabolic rate (BMR)

the minimum for an endotherm at rest, with an empty stomach, and under no stress (body size directly proportional, mouse uses more energy than elephant per 1 gram of body tissue)

torpor

decreased activity and metabolism

hibernation

long term torpor in the winter

estivation

long term torpor in the summer, decreased metabolic rate reduces energy requirements for animals and prevents starvation