Metabolism and survival Key Area 3: Metabolic Rate Flashcards
What is metabolic rate?
Metabolic rate is the quantity of energy used by the body over a given time. It is measured in kilojoules (or kilocalories)
What can metabolic rate be measured as?
Oxygen consumption per unit per time
CO2 production per unit per time
Energy production per unit per time
What is Basal metabolic rate? (BMR)
At rest, meaning in periods of inactivity the metabolic rate is known as the basal metabolic rate.
During BMR why does the body only need to use energy?
To keep vital organs such as the heart, lungs and brain functioning properly.
What increases the metabolic rate?
Activity.
Where is the Alveoli?
The alveoli are found at the end of each Bronchiole
Explain the complexity of lungs in amphibians.
Gas exchange occurs through skin, mouth cavity and lungs. (only in heavy exercise)
Their lungs are small, thin walled sacs that contain some alveoli.
describe the lungs in mammals and reptiles.
They possess a system of branching tubes that end in alveoli. The inner lining is thin and moist - giving a large surface area for gas exchange.
Describe lungs in birds.
Birds require more oxygen than other vertebrates (relative to their size) - as flying is a high energy consuming process.
They have lungs and several large air sacs - which act like bellows.
Birds do not possess alveoli - but have tiny channels called parobronchi -filled with capillaries which gas exchange occurs.
What are the two main low oxygen niches?
High altitudes and deep diving marine habitats.
What must diving animals cope with?
They must cope with both a limited supply of oxygen and an increase in pressure with increasing water depth.
What can have serious affects on the body at high concentrations?
nitrogen and oxygen. Nitrogen poisoning causes euphoria and delusions similar to a narcotic effect. The toxic affect of oxygen at high pressure can result in blackout or death.
What Is symptoms of high altitude sickness in humans?
vomiting, headache, fatigue, and difficulty in thinking clearly. In severe situations cerebral and pulmonary edema result from accumulation of fluid around the brain.
What is maximum oxygen uptake? (VO2 max)
It is the maximum volume of oxygen a persons body can take up and use during intense exercise.
How is VO2 max measured?
A person is fitted with an oxygen and carbon dioxide analyser and preforms the exercise on an ergometer such as a treadmill or exercise.
