Chapter 1- Homeostasis

Question 1

What does the lack of internal uniformity of homeostasis ?

Answer 1

1. the inside of the body is not uniform
2. Homeostasis mechanisms function key differences in the
   body

Question 2

What is the feedback systems, what is called ? and how many cycle of events does it go through ?

Answer 2

• a cycle of events in which the internal environment is
  
  1. monitored
  2. evaluated
  3. changed
  4. re-monitored
  5. re-evaluated

Question 3

What is the controlled condition ?

Answer 3

• the variable being monitored – B/p, Blood Sugar

Question 4

what is Stimulus ?

Answer 4

• whatever disrupts or changes the controlled condition
• disruptions can be internal or external .
  e.g Orthostatic hypotension;
  called postural hypotension — is a form of low blood
  pressure that happens when you stand up from sitting
  or lying down.
  Orthostatic hypotension can make you feel dizzy or
  lightheaded, and maybe even faint.
  e.g hot to cold or cold to hot

Question 5

What is homeostasis?

Answer 5

• the condition of balance in the body’s internal environment
  due to the constant interaction of the body’s many internal
  regulatory processes.
• the body is dynamic and it is constantly changing
• from the cells to the organ systems, all structure contribute to
  maintaining homeostasis
• as long as the body’s response can recover homeostasis, the status
  of normal is retained.
• when something disrupts homeostasis (e.g shifts in one direction),
  there are mechanisms that will have the opposite effect.
• most disruptions are mild and temporary and the return to
  homeostasis is relatively quick
• there are limits within which all the different parts of your body can
  and should function .
• homeostasis represent the ongoing processes that keep the internal
  environment within those limits.

Question 6

what are the components of the feedback system/loop ?

Answer 6

1. a sense or receptor
2. transmission pathways
3. a control Centre
4. an effector

Question 7

What are the characteristics of the sensor/receptor?

Answer 7

1. monitor changes in a controlled condition
2. detect chemical , electrical and mechanical changes
3. sends information to the control Centre (via transmission pathways)
   e.g baroreceptors - senses the B/p on the Aorta and other regions
   of the body.

Question 8

What is the characteristics of the transmission pathways?

Answer 8

1. the nervous and the blood vessel pathways(as well as their 
    signaling molecules)
2. relay messages between 
     - the sensor/receptor and; 
     - the control centre and; 
     - the effector

Question 9

The head quarter of the feed back system is called the control Centre? how does it work?

Answer 9

1. comprised of the nervous and endocrine sys. (hormone)
2. sets the range of values within which the controlled condition
   should be maintained.
3. evaluate and compares the input received from the sensor/ receptor
   against the set range.
4. determines the body’s responses to the change in the controlled
   condition
5. sends the commands (when needed) to the effector (via
   transmission pathways)

Question 10

What does the effector do?

Answer 10

• produces the response to given stimulus
• receive the commands from the control Centre
• produces the response that will change the controlled
  condition

Question 11

what is the characteristics of the negative feedback?

Answer 11

1. function to reverse the changes in the internal environment (respond to a disturbance by moving the controlled condition back towards the initial set range)
2. very stable
3. predominant system/loop

Question 12

Give an example of the negative feedback sys/loop?

Answer 12

• Stimulus (high blood pressure )
• Disrupting the homeostasis
• blood pressure (controlled condition)
• receptors (baroreceptors in certain blood vessels)
• nerve impulses send signals to
• the brain (control Centre)
• then the nerve impulses send signals to
• the heart (effectors)
• Response ( a decrease in the heart rate and the dilation of the
  blood vessels cause B/p to decrease)
• Return to normal B/P(normal homeostasis)

Question 13

What is the characteristics of the positive feedback?

Answer 13

1. function to strengthen changes in the environment (respond
   to a disturbance by moving the controlled condition farther
   from the initial set range)
2. mechanism that shuts down the response
3. inherently unstable
4. uncommon

e,g Oxytocin, prolactin , bleeding from a cut.

Question 14

In homeostasis, there are limits to how much the body can compensate ?True or False

Answer 14

True

Question 15

the body fuel is ATP ? True or False

Answer 15

True

Question 16

As we age , the ability to maintain and efficiently return to homeostasis decreases? True or False

Answer 16

True

Question 17

When do u notice homeostasis ? (in the short term & long term)

Answer 17

• if it is moderately affected , disease states can occur

- if it is severely affected then death is possible

Question 18

When do not notice the homeostasis?

Answer 18

• when it is mildly affected , you may not notice it (symptoms
  maybe mild)

Question 19

If part of the body is dysfunctional how does homeostasis interact ?

Answer 19

• it can’t or is less able to contribute to the maintenance of
  homeostasis
• homeostasis will be harder to maintain or may not be
  maintained.
• there are limits to how much the bod can compensate

Question 20

What is the adjustment of an organism to its environment ?

Answer 20

Adaptation

Question 21

The adjustment of an organism to counter balance a defect?

Answer 21

Compensation

Question 22

The body can change the parameters within which it is acceptable to function ? True or false

Answer 22

True

Question 23

If all controlled conditions remain within established limits, homeostasis is maintained and the body stays healthy? True or False

Answer 23

True