Chapter 1 Study Questions

Front 1

1. Functional integration

Back 1

Functional integration- How parts of the body work together at various levels of organization, and most importantly, how the entire organization works together

Front 2

3. Internal environment

Back 2

Internal environment- Fluids that surround cells and exist in blood

Front 3

3. External environment

Back 3

External environment: Unpredictable, changing environment outside the body to which the organism must physiologically adapt

Front 4

4. Extracellular fluid

Back 4

ECF- Fluid present in the blood and in the spaces surrounding cells

Front 5

4. Intracellular fluid

Back 5

Fluid inside the cells

Front 6

4. Interstitial fluid

Back 6

The ECF which lies around and between cells. Doesn't include plasma.

Front 7

4. Interstitium

Back 7

the space containing interstitial fluid

Front 8

5. Homeostasis

Back 8

Relatively stable condition of ECF that results from regulatory system actions. Necessary because a stable internal environment must be maintained. When homeostasis is lost for one variable, it may trigger a series of changes in one variable

Front 9

6. Explain how a steady-state is diff from an equilibrium.

Back 9

A steady-state is a system in which a particular variable must be added continuously to maintain a constant condition. In an equilibrium, the variable is not changing, but no input of energy is required to maintain constancy.

Front 10

7. Explain how feedback & feedforward loops are used to maintain homeostasis.

Back 10

The product of the causal-chain of a neg feedback loop stops the product's production.
Positive: promotes the product's production. Feedforward: one stimulus starts a causal-chain that activates another causal-chain ahead of time to avoid the need for a drastic response to the initial stimulus.

Front 11

8. Homeostatic set point

Back 11

A point the body aims to keep a function set at, e.g. a certain blood pressure point A significant variation from a set point triggers corrective action.

Front 12

9. Why can't all set points be maintained at the same time?

Back 12

Because so many properties of the internal environment are closely interrelated, so it's often possible to keep one property relatively stable only by moving others away from their usual set point.

Front 13

10. Explain how come homeostasis can be maintained even though set points aren't kept the same throughout the day.

Back 13

Any regulated variable will have a more or less narrow range of normal values depending on the external environmental conditions.

Front 14

11. Local response

Back 14

A local response is the result of a sequence of events proceeding from a stimulus. Unlike a reflex, the entire sequence only occurs in the area of the stimulus. Local responses provide individual areas of the body w/ mechanisms for self-regulation.

Front 15

13. List the four general means by which cells communicate

Back 15

Neurotransmitters, hormones, and paracrine or autocrine substances

Front 16

14. Target cells

Back 16

Cells acted on by a specific hormone

Front 17

15.

Back 17

missing

Front 18

16. Explain how come it may be beneficial to an organism for the homeostatic set points of specific parameters to be controlled by multiple systems.

Back 18

The adaptive value of such redundancy is that it provides much greater fine-tuning & also permits regulation to occur even when one of the systems is not functioning properly because of disease.

Front 19

17. Explain what is meant physiologically regarding a "pool" of substance within the body.

Back 19

The body's readily available quantity of a substance within the body. Pool concentrations depend not only upon the total amount of the substance in the body but also upon exchanges of the substance within the body.

Front 20

15. Explain how local homeostatic and whole-body homeostatic controls make use of the four general means of cellular communication.

Back 20

The four general means of cellular communication:
- hormones*
- nerves* (that act over large distances*)
- paracrine* & autocrine* signaling that acts over short distances*.

Hormones and nerves ex: (cold outside)
- Skin receptors sense and brain will integrate signal*
- Brain causes shivering, releases metabolism-altering hormones*

-Whole body mechanisms get entire body to react*

- Paracrine signaling: localized responses* like inflammation around a cut. Cells there release hormones that act over short distance to stimulate nearby cells' response*
- Autocrine: talks to itself* to reinforce* or inhibit* response*
- Local homeostatic responses: not entire body*, w/o CNS