Chapter 24 - Temperature Regulation And Metabolism Flashcards
Homeothermic
The ability to regulate our own temperature
Why is temperature regulation important in the human body?
It is important for maintaining homeostasis and proper care of enzymes
Core temp:
98.5
How is temperature maintained?
Radiation Convection Conduction Evaporation Metabolism
What happens on a hot day?
E is gained from the sun’s radiation
E is gained from conduction
E is gained from convection
E is gained from metabolism
E is lost by evaporation
E is lost by physiological functions: sweating, vasodilation
Behavior changes: light clothing, swimming, water intake, etc.
What is one function of the hypothalamus?
Temperature regulation
What are associated pathologies to temperature regulation?
Hyperthermia
Fever
Hypothermia
Hyperthermia
Heat gained exceeds heat lost.
Caused by: exercise, a hot day, fever.
Signs: heat exhaustion (over 99.7•F), hear stroke (over 104•F)
The cascade of events concerning hyperthermia
Sweating Dehydration Blood volume decreases Blood pressure decreases Heart rate goes up Hypothalamus still works Heat exhaustion Enzymes denature Stroke Hypothalamus stops working Sweating stops Most enzymes are destroyed Tired Coma Death
Fever
Due to: invading organism or substance
Caused by: pyrogens produced by WBC’s
Which: causes an increase in prostaglandin secretion
And: hypothalamus increases its set point
Hypothermia
Heat loss exceeds heat gain.
Caused by: a cold day or anesthesia
95• or lower
Slows enzymes
Cascade of events concerning hypothermia
Decreased heart rate Decreased respiratory rate Decreased metabolism Shivering Coma Death
Metabolism
Sum of all chemical reactions in the body
Catabolism
E release: breaking down
Anabolism
E gain: building up
What is the Energy in carbohydrates, lipids, and proteins used for?
Produce ATP via Oxidation-Reduction reactions
Metabolic rate
Total amount of E produced and used by the body per unit of time
Basal metabolic rate
E that runs the body at rest (60%)
Thermic effect of food
E needed for digestion (10%)
Muscle activity
E used for movement of skeletal muscles (30%)
Food consumption
Daily E input should equal daily E output to maintain a set weight
Recommended amounts of nutrients
Carbs- 60% daily kcals
Lipids- 30% daily kcals
Proteins- 10% daily kcals
What is the function of antioxidants?
To prevent formation of free radicals
Free radical
A chemical produced by metabolism that is missing electrons. It steals electrons from from chemicals in the cells, thus causing cellular damage.
ATP is formed from food via
Anaerobic and aerobic respiration
Anaerobic
Breaks down glucose
No O2
Produces either lactic acid or ethanol&CO2 + 2ATP (from glycolysis)
Does not use mitochondria
What are the phases of anaerobic respiration?
Glycolysis
Fermentation (of lactic acid OR ethanol)
Aerobic respiration
Breaks down glucose O2 present Produces Co2, H2O. Yields 40 ATP minus 2 ATP used up in glycolysis Occurs in mitochondria
What are the phases of aerobic respiration?
Glycolysis
Citric acid cycle
Electron transport chain
Glycogenesis
Excess glucose forms glycogen for storage
Glycogenysis
Glucagon breakdown to harvest glucose
Lipogenesis
Glucagon storage is full… So glucose and amino acids form lipids
Gluconeogenesis
Formation of glucose from amino acids + glycerol (proteins and fats)
