Ch. 1

Front 1

internal environment

Back 1

fluid that surrounds the cells inside the body, including fluid in the bloodstream that surrounds blood cells; synonymous with extracellular fluid

Front 2

absorption

Back 2

In GI tract, the water, inorganic salts, and nutrients obtained from digested food are transported from the lumen to the bloodstream

Front 3

secretion

Back 3

in aid of digestion of food, the stomach uses materials from the blood to produce acids and proteins that are then transported into the lumen.

Front 4

filtration

Back 4

Happens in kidneys
fluid from bloodstream enters tubules.

Front 5

Reabsorption

Back 5

fluid travel along tubules, and needed materials (H2O, inorganic salts, and nutrients) are selectively transported back into the bloodstream.

Front 6

Secretion

Back 6

At the same time as reabsorption, unneeded materials are selectively transported from the bloodstream into tubules.

Front 7

Excretion

Back 7

fluid that reaches the end of the tubules make up the urine which elminated from body.

Front 8

water

Back 8

What's the most abdundant substance in the body?

acts as a solvent w/solutes.

Front 9

solutes

Back 9

inorganic ions
sugars
amino acids
Large molecules (proteins)

Front 10

cell membranes

Back 10

ICF and ECF are separated by ____ _______.

Front 11

ICF

Back 11

proteins and potassium

Front 12

ECF

Back 12

few proteins
high sodium

Front 13

Homeostasis

Back 13

maintenance of CONSTANT conditions in the internal environment

Front 14

Total body water (TBW)

Back 14

the total volume of fluid enclosed within the outer epithelial layer. Includes water that is found inside cells (ICF) and outside cells (ECF).

Front 15

Intracellular fluid (ICF)

Back 15

fluid inside cells

Front 16

ECF

Back 16

Fluid outside cells

Front 17

Plasma

Back 17

in blood
noncellular part of the blood
rich in proteins

Front 18

Interstitial fluid (ISF)

Back 18

The portion that is present OUTSIDE the blood and that bathes most of the cells in the body
few proteins

Front 19

Capillaries

Back 19

smallest and most numerous blood vessels
highly permeable to most solutes except proteins.

Front 20

Homeostatic regulatory mechanisms

Back 20

mechanism works to resist changes in the internal environment
has it's limitations even when it's undamaged by disease or trauma and is functioning normally.

Front 21

Negative Feedback

Back 21

Homeostatic regulatory mechanisms follow same pattern
if regulated variable increases, the system responds by making it decrease.
if it decrease, it responds to make it increase
work to resist changes in the internal environment

Front 22

Regulated variable

Back 22

something that must stay within narrow limits.
ex. Body temp., Potassium, sodium, and calcium.
kept constant by homeostatic regulatory mechanisms

Front 23

Set point

Back 23

Homeostatic regulatory mechanisms that make adjustments only when they DETECT a difference btwn. the actual value of the regulated variable and the normal "desired" value.

Front 24

Error signal

Back 24

Any difference btwn. the actual value and the set point sets off an _____ ______.

Front 25

Sensors

Back 25

cells that are sensitive to the variable in question.
This is the way that Homeostatic regulatory mechanisms can detect regulated variable.

Front 26

Chemoreceptors

Back 26

sensitive to concentrations of oxygen and carbon dioxide in the blood

Front 27

Thermoreceptors

Back 27

sensitive to temperature

Front 28

Integrating center

Back 28

often a particular set of neural circuits in the brain
compares the regulated variable variable to the set point and plans the right response

Front 29

input

Back 29

Sensors relay signal to integrating center

Front 30

output

Back 30

Integrating center relays signals to the cells, tissues, or organs that bring about the final response.

Front 31

Thermoregulatory center

Back 31

the region responsible for temp. regulation

Front 32

Positive feedback

Back 32

the response of the system goes in the same direction as the change that sets it in motion.

Front 33

LH surge

Back 33

triggers ovulation

Front 34

Thermoregulation

Back 34

utilization of feedback mechanisms to maintain normal body temp.

Front 35

hypothermia

Back 35

Prolonged exposure to very cold temps can cause body temp to fall below the set point

Front 36

Hyperthermia

Back 36

overextertion or exposure to very high environmental temps can cause body temp to rise above the set point.

Front 37

Homeothermic

Back 37

humans and other mammals are less affected by changes in the ambient temp because they have the ability to maintain their body temp within a fairly narrow range

Front 38

Poikilothermic

Back 38

animals and mammals who are not homeothermic.

Front 39

heat loss mechanisms

Back 39

radiation
conduction
evaporation

Front 40

Radiation

Back 40

transfer of thermal energy in the form of electromagnetic waves
when object is warmer than its surroundings, it absorbs and loses heat
if an object is cooler than it surroundings, it absorbs more energy than it emits and gains heat.
ex. heat from fire

Front 41

Conduction

Back 41

transfer of thermal energy btwn. objects that are in direct contact with each other.
touching something cold can make you feel cold

Front 42

Evaporation

Back 42

the process that converts it from liquid form to gaseous form absorbs thermal energy.
ex. takes place on skin, in lungs and mouth
more water evaporates which carries away more thermal energy.

Front 43

Insensible water loss

Back 43

happens in skin, lungs, and mouth on a continual basis without your being aware of it.

Front 44

Sweat

Back 44

a salt-containing solution secreted by numerous small sweat glands in the skin.

Front 45

Convection

Back 45

the transfer of heat from one place to another by moving gas or liquid, contributes to heat loss on a windy day.
under still conditions, the air that is closer to your skin warm up due to the absorption of heat from the body's surface (forms a "blanket" around body)
warmer air slows down heat loss
when windy the "blanket" is reduced which leads to heat loss

Front 46

hypothalamus

Back 46

a region located in the base of the brain just above the pit. gland.

Front 47

central thermoreceptors

Back 47

send input to brain center (brain, spinal cord) and monitor the temp. from inside body (core temp.)

Front 48

Core temperature

Back 48

temp deep within the body

Front 49

Peripheral receptors

Back 49

located in the skin whose temp is usually well below core temp and is more variable.
enables us to sense the temp of the environment

Front 50

effectors that vary the rate of heat production or loss

Back 50

sweat glands
blood vessels in skin
skeletal muscle

Front 51

sweat glands

Back 51

control evaporative heat loss increasing or decreasing sweat production

Front 52

Blood vessels in the skin

Back 52

which control conductive and radiative heat lossby increasing or decreasing blood flow to the skin

Front 53

skeletal muscle

Back 53

which control heat production through shivering

Front 54

shivering

Back 54

rapid bursts of involuntary contractions that generate heat as a metabolic by product

Front 55

thermoneutral zone

Back 55

outside temp is within a narrow range (25 to 30 C)
blood flow to skin can make normal adjustments till core temp is normal

Front 56

thermoregulatory centers

Back 56

When core temps change ________ ______ send signals to effectors.

Front 57

Negative feedback response to core temperature

Back 57

1. Decrease sweat production
2. Decrease blood flow to skin
3. Stimulate shivering

Front 58

Fever

Back 58

elevation of body temp usually during illness. Not from failure of thermoregulatory system. Set points not being reset cause fever.
bacterial & viral infections stimulate WBC's to proliferate chemical substances which rise set point, and act as pyrogens.

Front 59

Chills

Back 59

↑ muscle activity used to ↑ body temp

Front 60

Sweats

Back 60

↑ evaporative cooling to ↓ body temp

Front 61

pyrogens

Back 61

fever inducers