Homeostasis

Question 1

Define homeostasis:

Answer 1

An internal condition maintained by internal responses that compensate for changes in the external environment; and dynamic condition

Question 2

Define active hyperemia

Answer 2

-increased blood flow through a tissue

Question 3

What are intrinsic controls?Give an example

Answer 3

Vasodilators

Question 4

What is an example of a vasodilator and how does it work?

Answer 4

NO; when blood oxygen levels fall, endothelial cells in blood vessel walls synthesize and release NO; No activates an enzyme that relaxes neighboring smooth muscles; This dilates blood vessels, increases blood flow

Question 5

What is the primary mechanism of homeostasis?

Answer 5

negative feedback

Question 6

In the negative feedback mechanism, the response of the system..

Answer 6

cancels or counteracts the effect of the original environmental change

Question 7

Break down the process of sensory transduction

Answer 7

stimulus is converted into an AP
-AP is transmitted along axons towards the CNS where it is integrated

Question 8

How do baroreceptors work?

Answer 8

they send signals (AP) to the brainstem and the brain stem sends signals via autonomic nervous system to elicit changes

Question 9

Baroreceptors decrease/increase their rate of firing when blood pressure drops

Answer 9

decrease (example when a person stands up blood pressure drops)

Question 10

What are chemoreceptors and where are they found?

Answer 10

found in the aorta and carotid arteries(and other locations)
-can detect O2 content in the blood

Question 11

What is respiratory acidosis:

Answer 11

decreased or obstructed respiration causes increase blood CO2 and decreased pH

Question 12

What is metabolic acidosis:

Answer 12

occurs if the kidneys are not removing enough acid from the body

Question 13

What is ketoacidosis and what are some examples?

Answer 13

the body fails to adequately regulate ketones
-diabetes (type 1) and alcoholic ketoacidosis

Question 14

What is an example of Alkalosis

Answer 14

hyperventilation

Question 15

Ectotherms obtain heat from… while endotherms…

Answer 15

obtain heat from the environment
-can generate heat metabolically

Question 16

How else does an animal change its conductance to heat?

Answer 16

-redirect blood flow; if the temp outside is cold the blood can be directed to avoid the surface which results in the body being more insulated because the blood is flowing beneath a fatty layer of skin
-the body temp is warmer the blood can be redirected to the surface and heat can flow out more easily which would increase conductance

Question 17

When you feel hot your blood vessels… and when you feel cold your blood vessels

Answer 17

dilate, constrict

Question 18

What concept occurs so the isolated part of the body doesn’t change the temperature of the rest of the body?

Answer 18

-Counter-current flow

Question 19

Countercurrent exchange ensures…

Answer 19

gradients that facilitate the maximal amount of heat retention

Question 20

Temperature regulation is controlled by…

Answer 20

triggered by thermoreceptors
-integrated by the hypothalamus

Question 21

What thermoreceptors receive signals when there’s a change in skin temperature

Answer 21

peripheral thermoreceptors in the skin

Question 22

What thermoreceptors receive signals when there’s a change in core temperature

Answer 22

central thermoreceptors in the hypothalamus, abdominal organs, and elsewhere

Question 23

What happens when environmental temperatures go to the extreme?

Answer 23

-below freezing: lipid bilayer changes from liquid to frozen gel, disrupts cell function and destroys organelles
-high temp: proteins and nucleic acids unfold due to an increase in kinetic energy of molecules

Question 24

When there is vasoconstriction this means..

Answer 24

less heat is conducted from the blood, thru the skin, to the environment, which means heat loss is reduced

Question 25

What are the four basic tissues and their functions?

Answer 25

epithelial: lines body structures and cavities; forms protective, secretory and absorptive covering
-connective: support
-muscle: movement
-nervous: transmits information

Question 26

What are the three common shapes of epithelial cells?

Answer 26

squamous, cuboidal, columnar

Question 27

Endothelium

Answer 27

the thin layer of cells, that line the interior surface of blood vessels

Question 28

What are the six types of connective tissue?

Answer 28

loose connective tissue, fibrous connective, cartilage, bone tissue, adipose, blood

Question 29

What are the three types of muscle?

Answer 29

-skeletal, cardiac, smooth