Year 8 - Physiology Flashcards
What is aerobic respiration? What is the word equation?
Respiration that takes place with oxygen
Oxygen + Glucose → Carbon Dioxide + Water (+ energy)
What is the difference between respiration and breathing?
Respiration is a chemical reaction to produce energy
Breathing is the physical movement of air in and out of the lungs
In which organelle does respiration occur?
Mitochondria
What is anaerobic respiration? What is the word equation?
Respiration that takes place without oxygen
Glucose → Carbon Dioxide + Lactic Acid (+ energy)
Why do we sometimes use anaerobic respiration? Is it better than aerobic respiration?
When we no longer have enough oxygen in our bodies for respiration (Less efficient)
Explain the process of breathing in
The intercostal muscles contact and diaphragm contracts, assuming a flatter shape, increasing the volume of the thoracic cavity. This decreases the pressure inside the lungs, drawing in air to equalise the pressure
Explain the process of breathing out
The intercostal muscles and diaphragm relax, moving the ribs down and in. The diaphragm moves up, decreasing the volume of the thoracic cavity and increasing the pressure, which results in the air flowing out of the lungs
What is gas exchange?
A non energy consuming process that takes in oxygen for respiration and excreting carbon dioxide as a waste product
Describe the process of gas exchange
Oxygen in the alveolus air space moves through the capillaries into the red blood cells by diffusion. Because the walls of the alveolus and capillaries are one cell thick, this makes gas exchange faster
Explain the adaptations of alveoli
Large surface area for easier gas exchange. One cell thick walls so diffusion takes place easily. Good blood supply to take the oxygen to the rest of the body
What is the function of plasma?
Carries glucose, carbon dioxide and hormones
What is in blood?
Red blood cells, platelets, white blood cells, plasma
What is the function of red blood cells?
Carry oxygen around the body
What is the function of platelets?
Helps to clot the blood
What is the function of white blood cells?
Defends against pathogens by either engulfing them or producing antibodies
What are the structures of white blood cells, plasma, platelets and red blood cells?
WBC - Flexible
Plasma - Water with many dissolved substances
Platelets - No nucleus, small fragments of cells
RBC - No nucleus, biconcave shape
What is a muscle?
A tissue in the body that contracts and relaxes to move bones
What is an antagonistic pair of muscles?
A pair of muscles that work against each other
What are tendons?
Cords that attach the muscles to the bones
Why do muscles work in pairs?
Alone, a muscle can contract to pull a bone, but cannot move it back to it’s original position without the help of another muscle
Explain how triceps and biceps work
When the bicep contracts, it gets shorter and fatter, the tricep relaxes and pulls on the bone, raising the arm. When the bicep relaxes, the tricep gets shorter and fatter, lowering the arm
What type of skeleton do vertebrates have?
An endoskeleton (Internal skeleton)
What type of skeleton do invertebrates have?
An exoskeleton (External skeleton)
What are the four functions of a skeleton?
Shape
Movement
Protection
Production of blood cells
