B2.2 Flashcards
What is respiration
An enzyme catalysed reaction that releases the energy needed for us to use and live
What happens in aerobic respiration
The glucose in the body reacts with oxygen to form carbon dioxide plus water and energy
Glucose + oxygen —> carbon dioxide + water + energy
What does blood need to carry
Glucose and oxygen to the cells and carbon dioxide away from them
What happens in diffusion
When particles of a substance spread out, moving from an area of high concentration to an area of low concentration. They diffusé down a concentration gradient
What are alveoli and purpose. What is gas exchange
They are tiny sacs that make up the lungs and are surrounded by capillaries. Oxygen comes into the lungs and diffuses through the alveoli and into the blood. As oxygen enters the blood, carbon dioxide leaves it, this is gas exchange
Why does exercising increase heart rate
When you exercise, muscle cells are using more energy as muscles are moving more. This means they need more oxygen and need more carbon dioxide to be removed. To do this faster, you breath faster and the heart beats faster to get the blood with oxygen to the muscles fast and to remove the carbon dioxide fast
What is stroke volume
The volume of blood pumped per beat
What is cardiac output
The volume of blood circulated in the body in a given time, worked out by
Cardiac output = stroke volume x heart rate
What happens in anaerobic respiration
Occurs when not enough oxygen
Glucose —> lactic acid + less energy
What is epoc
Excess post exercise oxygen consumption. It’s when the body needs to keep breathing heavily after exercise to get oxygen to break down the lactic acid build up from anaerobic respiration
What is the recovery time
The time taken for pulse to return to resting levels after exercise
What is photosynthesis
The process plants use to make glucose from water and carbon dioxide for energy, using the sun
Carbon dioxide + water —> glucose + oxygen
How does photosynthesis work
Photosynthesis is a series of complex catalysed reactions. It occurs in chloroplasts in the leafs. Light enters the leaf and into the chloroplasts. Chlorophyll in the chloroplasts convert light energy into the chemical energy stored in glucose
How is starch detected
Iodine solution turns leafs dark blue if starch. Only places with chlorophyll in the leaf will go dark
Adaptations of leafs
Lots of chlorophyll for photosynthesis. Large broad thin shape for large surface area so absorb as much light as possible. Underneath are stomata, stoma, these absorb carbon dioxide and release oxygen, doing both through diffusion. Lots of air sacs to give the cells a large surface area to volume ration for efficient gas exchange