Human body systems, Year 8: respiration and heart rate：全部卡片
整套按顺序列出——孩子看到之前，您可以先通读一遍。
- Where in the body does respiration take place?
In every living cell
提示Not just in the chest: think much smaller, and all over the body.
为什么Each cell needs its own supply of energy, so each one carries out respiration for itself.
- Which process in cells releases the energy stored in glucose?
Respiration
提示It is the reason you need food as well as air.
为什么It is a chemical reaction. In its usual form, glucose reacts with oxygen and energy is released for the cell to use.
- Is 'moving air into and out of the lungs' a description of breathing or of respiration?
Breathing
提示The other one is a chemical reaction.
为什么Breathing is a physical movement of the ribs and diaphragm. Respiration is the reaction in cells that uses the oxygen which breathing brings in.
- Why does the body need a constant supply of oxygen?
Cells use it in respiration to release energy
提示Think about what has to happen to the glucose from your food.
为什么Without oxygen, cells cannot get enough energy from glucose. Brain cells begin to be damaged within minutes.
- A person holds their breath for 20 seconds. Does respiration in their cells stop?
No — it carries on
提示The blood still holds a store of oxygen.
为什么Cells respire all the time, awake or asleep. Holding your breath stops fresh air arriving, but the reaction continues with the oxygen already in the blood.
- What does a pulse rate measure?
The number of heartbeats per minute
提示You can feel it at your wrist or neck.
为什么Each beat of the heart pushes a surge of blood along the arteries, and you can feel that surge wherever an artery runs near the skin.
- A pupil counts 18 beats in 15 seconds. What is their heart rate in beats per minute? (number only)
72
提示There are four lots of 15 seconds in a minute.
为什么18 × 4 = 72. Counting for a quarter of a minute and multiplying up is quicker than counting for the full minute.
- Why does your heart rate rise during exercise?
Muscles need more oxygen and glucose
提示Think about what the cells doing the work are running short of.
为什么Harder-working muscles respire faster. The heart beats more often so that blood delivers supplies and removes carbon dioxide more quickly.
- After exercise stops, what happens to the heart rate over the next few minutes?
It falls back to its resting rate
提示The demand for oxygen has dropped again.
为什么Once the muscles need less, the heart slows. The time this takes is called the recovery time, and it is shorter in fitter people.
- In a heart-rate investigation, why is the pulse taken before the exercise as well as after it?
To give a resting value to compare with
提示Without it you cannot tell how much changed.
为什么The effect of the exercise is the difference between the two readings. One reading alone says nothing about the change.
1★ KS3-BIOL-HUM-0013
2★ KS3-BIOL-HUM-0014
3★ KS3-BIOL-HUM-0015
4★ KS3-BIOL-HUM-0016
5★ KS3-BIOL-HUM-0017
6★ KS3-BIOL-HUM-0018
7★ KS3-BIOL-HUM-0019
8★ KS3-BIOL-HUM-0020
9★ KS3-BIOL-HUM-0021
10★ KS3-BIOL-HUM-0022