Metabolism

Question 1

Kilcarlories

Answer 1

A kilocalorie is equivalent to 1000 valories and is the amount of energy needed to raise 1 kilogram of water by 1 degree Celsius

Question 2

Basal Metabolic Rate & Factors that Affect it

Answer 2

Defined as the amount of energy expended by the human body while at rest when the digestive system is inactive

BMR is meant to represent the minimum energy level required by the human body to keep the vital organs functioning

Question 3

Normal range of body temperature

Answer 3

Internal body temperature is kept at a steady 37^oC (98.6^oF)

The efficiency of the human body is optimized between the temperature range of 36^oC (97^oF) and 40^oC (104^oF)

Hyperthermia- above this range

Hypothermia- below this range

Question 4

Four mechanisms to remove heat

Answer 4

1. Radiation
2. Conduction
3. Convection
4. Evaporation

Question 5

Radiation

Answer 5

All objects emit infrared radiation, a form of heat energy

This energy is below the level of visible light therefore we cannot see it

Half our daily heat loss occurs through radiation

Question 6

Conduction

Answer 6

Involves the direct transfer of heat energy through contact

Sit on a cold metal chair, your heat energy is transferred directly to the chair

Question 7

Convection

Answer 7

When our body conducts heat energy to the air molecules around us, we use the term convection

As the air molecules near the surface of our skin are warmed, they rise away and are replaced with cooler molecules and the process begins again.

Question 8

Evaporation

Answer 8

As water evaporates, it changes from a liquid to a gas by absorbing energy thus cooling any surface upon which this happens

At rest, about 20% of the body’s daily heat loss occurs through evaporation (insensible water loss) across our skin and through our respiratory tract

Question 9

Hypothalamus

Answer 9

Hypothalamus has an internal memory where the optimal body temperature information is stored

Temperature rises, the hypothalamus sends the signal for vasodilatation and sweating.

Temperature falls, the hypothalamus sends the signals for vasoconsriction, piloerection and shivering

Question 10

Fever

Answer 10

Term for an increase in internal body temperature to levels above normal

One of the body’s mechanims to try to neutalize the perceived threat inside the body be it bacteria or virus

Fever present if: Rectal or otic (ear) over 38.0^oC (100.4^oF)

Oral over 37.5^oC (99.5^oF)

Axillar (under the arm) over 37.2^oC (99.0^oF)

Recover faster from infections and illness, some immunological (chemical) recations are sped up, some pathogens (infection fighters) will not function in the body, WBC function more efficiently and improves healing process