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1
Q

Themes of Physiology

A
Physical-chemical basis of body function
structure function relationships 
energy use
homeostasis 
integration
2
Q

Physical-chemical Basis of body function

A

focus on MECHANISM: how the body works

3
Q

Structure-function relationships

A

Body function depends on structure at all levels of biological organization
Cell basic unit of life
organism is the most highly integrated level

4
Q

Energy Use

A

life requires a continuous input of chemical energy

body cells obtain energy

5
Q

Homeostasis

A

maintenance of relatively constant internal conditions in the body
central principle of physiology

6
Q

Integration

A

Body systems are functionally connected and work together

7
Q

Integration of organ systems

what do they do and what controls them, role of circulatory system

A

OS work together to support body function
OS share a common internal environment; some organ systems have surfaces that contact the external environment
Nervous system and endocrine system control other organ systems
circulatory system transports and exchanges substances w/ other organ systems

8
Q

External environment

A

Includes lumen of hollow organs that open to outside
Part of external environment
respiratory, digestive, urinary, reproductive

9
Q

Extracellular fluid (ECF)

A

Internal environment
contains interstitial fluid (11L) and blood plasma(3L)
1/3 of total body water
major solutes: Na+, Cl-, some organic molecules
Functions as buffer between cells and external environment

10
Q

ECF Is high in _ and low in _

A

high in Na+

Low in K+

11
Q

Intracellular fluid (ICF)

A

2/3 of total body water
major solutes K+ and organic molecules A-
contained in trillion of cells

12
Q

Intracellular fluid is high in _ and low in _

A

low Na+

high K+

13
Q

Plasma Membrane

A

separates ICF and ECF
maintains different composition of ICF and ECF by selective permeability and molecular transport
prevents easy movement of ions

14
Q

Epithelium

A

Forms boundary between internal environment (ECF) and external environment
A protective barrier
exchanges surfaces
functions in absorption, secretion, gas exchange

15
Q

Free Surface

A

faces external environment (or lumen of hallow organs)

16
Q

Law of Mass balance (steady state process)

A

open system, INPUT=OUTPUT to maintain a constant level

Example: input (food+drink+metabolism) = output (urine+feces+evaporation)

17
Q

What is required to maintain homeostasis

A

ENERGY

ex. Na-k pump uses ATP to maintain [Na+] and [K+] of ICF and ECF
ex. cellular respiration

18
Q

Why is the ECF regulated

A

to maintain suitable conditions for cells

19
Q

7 essential variables

A

body temp, arterial blood pressure, pH, Po2, Pco2, blood, plasma osmolarity

20
Q

Body Temperature

A

37*C

21
Q

Arterial Blood Pressure

A

120/75 mm Hg

Mean = 90 mm Hg (millimeters of mercury)

22
Q

Arterial pH

A

7.4, slightly alkaline

23
Q

Arterial Po2

A

P= pressure
pressure of o2
100 mm Hg

24
Q

Arterial Pco2

A

carbon dioxide pressure

40 mm Hg

25
Q

Blood [glucose]

A

when fasting

90 mg/dL

26
Q

Plasma osmolarity

A

290 mOsm (concentration of all dissolved substances in plasma)

27
Q

Control of homeostasis

A

Negative feedback control maintains homeostasis

usually regulated by nervous and endocrine systems

28
Q

set point

A

optimum value/normal value

variable are regulated around a set point

29
Q

Direction of response

A

corrective response is in the opposite direction during negative feedback
ex: heat gain means heat loss to decrease body temp
heat loss means heat gain to increase body temp

30
Q

If you are too Hot what happens

A

the skin are hypothalamus detect that you are too hot (sensors)
sweat glands release sweat and vasodialation occurs
(effectors)
body temperature decrease (response)

31
Q

Positive feedback

A

non-homeostatic
results in rapid change of variable
Not very common

Ex. LH surge triggers ovulation