Slides in this set
2.1 The Circulatory System
The heart is a muscular organ that pumps blood around the body. The heart
pumps blood to the LUNGS where it GAINS OXYGEN and LOSES CARBON
DIOXIDE. After returning to the heart it is them pumped to the rest of the
- Arteries TAKE OXYGENATED blood FROM the heart.
- Veins BRING DEOXYGENATED blood TO the heart.
- Capillaries are tiny vessels between the arteries and veins. They carry the
blood through the organs and allow the exchange of substances with all the
living cells in the body.
Heart, Artery, Vein, Capillary, Circulation.…read more
2.2 Transport in Blood
Red blood calls are full of a pigment called HEAMOGLOBIN. In the lungs,
heamoglobin combines with oxygen to form OXYHAEMOGLOBIN.
Where the cells are respiring, the oxyhaemoglobin breaks back down releasing
the oxygen for respiration. Red blood cells have NO NUCLEUS so that more
haemoglobin can be packed into them.
The blood plasma transports:
- C02 to the lungs.
- The SOLUBLE products to digestion to all living cells in the body.
- Urea (made by the liver) to the kidneys for excretion.
Haemoglobin, Oxyhaemoglobin, Plasma.…read more
2.3 The Effect of Exercise on the
When you exercise, your muscles need more energy so that they can contract.
You need to increase the rate at which oxygen and glucose reach the muscle
cells. You also need to remove carbon dioxide quickly.
The heart rate increases and the blood vessels supplying the muscles DILATE.
This allows more blood containing oxygen and glucose to reach the muscles.
Your breathing rate and the depth of each breath also increases. This allows a
greater intake of oxygen and realise of carbon dioxide at the lungs.
You may also use up GLYCOGEN, a storage compound of glucose, present in
Dilate, Rate, Glycogen.…read more
2.4 Anaerobic Exercise
If you use muscles over an extended period of time then they will get tired or
fatigued. When your muscles cannot get enough oxygen for aerobic
respiration, they start to respire anaerobically.
- This inefficient and produces LACTIC ACID as a waste product.
- Lactic acid causes fatigue (tiredness). When the exercise has finished, this
lactic acid must be completely broken down. You therefore still need to take
in a lot of oxygen to do this. This is known as OXYGEN DEBT. The oxygen
oxidises lactic acid into carbon dioxide and water.
Fatigue, Anaerobic, Lactic Acid, Oxygen Debt.…read more
2.5 The Human Kidney
The body has 2 kidneys. They FILTER the blood, excreting substances the body
doesn't want, and keeping those substances that he body needs.
- The kidney is a very important organ of homeostasis and is involved in
controlling the loss of water and mineral ions from the body, as well as
getting rid of urea. The kidneys have a very rich blood supply.
After FILTERING the blood, all the of sugar and many of the dissolved ions and
water needed by the body are REABSORBED. All of the urea and some ions
dissolve in the remaining water and are excreted in the urine.
- Sugar and dissolved ions may be reabsorbed against the concentration
gradient. If they are, then the process is active transport and requires
Filter, Reabsorb, Excrete, Active Transport.…read more