KA2.3 Flashcards
(24 cards)
Describe ‘Metabolic rate’
the quantity of energy used by the body over a given time.
3 ways Metabolic rate can be measured.
Oxygen consumption
Carbon dioxide production
Energy production (as heat)
Describe a ‘closed’ circulatory system.
Blood is contained in a continuous circuit of blood vessels and is kept moving by a muscular pump, the heart.
Describe a ‘single’ circulatory system.
Blood passes through the heart once for one complete circuit.
Describe a ‘double’ circulatory system.
Blood passes through the heard twice for each complete circuit.
Why is a double circulatory system more efficient than a single system?
Double pumps blood at a higher pressure which ensures a more vigorous flow to all parts of the body.
Describe an ‘incomplete’ circulatory system.
Mixing of oxygenated and deoxygenated blood occurs.
Which type of vertebrate has a SINGLE circulatory system?
Fish
Which types of vertebrates ha DOUBLE COMPLETE circulatory system? (2)
Birds
Mammals
Which types of organisms have a DOUBLE INCOMPLETE circulatory system? (2)
Amphibians
Reptiles
Why is having an incomplete system not much of a problem in AMPHIBIANS?
Blood returning to hear has been partly oxygenated through gas exchange through their moist skin.
Why is having an incomplete system not much of a problem in REPTILES?
Little mixing of blood occurs as their ventricle is partly divided by a septum.
Describe a ‘complete’ circulatory system.
2 ventricles are completely spererated by a septum so no mixing of oxygenated and deoxygenated blood occurs.
Whys is the DOUBLE COMPLETE circulatory system most efficient.
Allows endothermic vertebrates to deliver large amount of oxygen to respiring tissues, they release heat during metabolism which keeps the organisms body warm.
When do amphibians only use their lungs?
During vigorous activity.
What do amphibians usually use to exchange gas instead of lungs? (3)
Skins
Mouth
Cavity
Describe the structure of an amphibians lungs.
Small
thin walled sacs which contain some alveoli
TRUE or FALSE
- amphibians surface area of lungs is smaller compared to other vertebrates.
True
Reptiles and —- possess a system of branching —– that end in ——
1 - Mammals
2- Tubes
3- Alveoli
What creates a large surface area for gas exchange in in Reptiles and Mammals.
The thin, moist inner lining of alveoli.
Why do birds require the most oxygen for size?
They fly so are the most active vertebrate.
What happens during inhalation of a bird?
Posterior sacs fill with fresh air.
Anterior sacs fill with stale air from lungs.
Describe what happens during exhalation in birds.
Fresh air passes from posterior sacs to lungs.
Stale air passes from anterior sacs to external enviroment.
What do birds contain instead of alveoli?
Parabronchi
