Ch 1 C

Question 1

Homeostasis

Answer 1

• Body’s ability to maintain a relatively stable internal environment in response tochanging internal or external conditions

Question 2

Variables

Answer 2

Conditions that change
Ex temp vol chemical content

Question 3

Set Point

Answer 3

• Ideal normal value
  _ homeostatic mechanisms like sweating or shivering normally maintain body temp hear an ideal norm value

Question 4

Coordinated activity of the organ systems is necessary for. normal function

Answer 4

Ex various systems involved in . digestion of food to removal of waste products from the food
-dysfunction in one organsysten can have major effects on other systems
Ex heartattack →inadequate blood circulation → brain &kidney malfunction

Question 5

Components of a homeostatic control system

Answer 5

• body maintains homeostasis by utilizing homeostatic control systems that have 3 important components
• receptor
• control center =
• effector =

Question 6

Homeostatic control mechanism

Answer 6

Stimulus:
Receptor:
Control center:
Effetotor ‘:

Question 7

Types of homeostatic control systems

Answer 7

Negative feed back
Positive feedback

Question 8

Negative feedback

Answer 8

_ Self limiting
- maintains the variable w/in a normal range by moving the stimulus in the opposite direction
Ex= maintaining l regulating body temp shivering or sweating

Question 9

Positive feedback

Answer 9

• uncontrollable
• amplifies the stimulus in the same direction
• ex= breastfeeding stimulus → baby suckles the breast → receptor sensory receptor in the skin of the breast detect suckling; sends impulse from the hypothalamus signals posterior pituitary torelease oxytocin → stimulates milk ejection from breast

Question 10

Important characteristics of homeostatic systems

Answer 10

• They are dynamic
  _ the control center- is generally the nervous system or the endocrine
  -3 components receptor / control center and effector
• . Failure of system → homeostatic imbalance or disease

Question 11

What happens when homeostasis is disrupted / what disrupts homeostasis

Answer 11

_ Can result death
- Disease disrupts homeostasis

Question 12

Are most homeostatic systems of the body regulated by neg or POS feed back

Answer 12

Negative feedback

Question 13

What happens @ the setpoint

Answer 13

The variable is maintained w/in a norm level

Question 14

Negative

Answer 14

’ Means are deviation from set pt is made smaller or resisted
Ex maintaining normal bp to ensure that tissue homeostasis = maintained

Question 15

Receptor

Answer 15

= monitors the value a variable

Question 16

Control center

Answer 16

part of the brain, establishes set pt around which the variable is maintain.

Question 17

Effector

Answer 17

such as the heart can change value of the variable
Ex blood pressure depended by hr

Question 18

Stimulus

Answer 18

changes in a variable that is regulated ( ex: temp )

Question 19

Receptor

Answer 19

structure that detec.ts the stimulus (ex sensory neurons in the skin)receptor sends input info to the control center if receptor. &. cc = separate

Question 20

Control center

Question 21

Effector

Answer 21

: structure ex: muscle that brings a change to the stimulus→ homeostasis restored