Medical Science

Question 1

Recall the differences between cells, tissues and organs

Answer 1

Cells: the basic units of life
Tissue: a group of cells make tissue
Organs: tissues work together to make up organs. Which then make up organ systems.

Question 2

Describe how oxygen gets to the cells (diffusion)

Answer 2

Diffusion requires no energy. Substances such as oxygen and glucose move into and out of cells across the the cell membrane by diffusion. Molecules will move into the cells because there is a higher concentration of oxygen molecules outside the cell compared to inside the cell. Diffusion particles move from high to low concentration.

Question 3

Explain why oxygen is needed for life processes

Answer 3

Oxygen is needed for organisms to grow, repair, reproduce, and turn food into energy.

Question 4

Recall the word equation for respiration

Answer 4

Glucose + oxygen –> energy (ATP) + carbon dioxide + water

Question 5

Name the key structures and functions for the respiratory system

Answer 5

Mouth/Nose
Epiglottis
Trachea
Bronchi
Bronchioles
Alveoli: small air sacs in the lungs. typically an adult has 400 million alveoli’s. Oxygen diffuses from the alveoli to the blood vessels which then carries the oxygen to the cells. It then diffuses from the blood into the cells, where it is used for respiration. in the reverse carbon dioxide diffuses from the cells to the blood then from the blood to the alveoli and is exhaled from the body.
Diaphragm
Ribs
Inter-coastal muscles: Muscles between the ribs. To raise the rib cage upwards and outwards when we breathe in.

Question 6

Label the diagram of a mammalian lung

Question 7

Describe the importance of the respiratory system

Answer 7

The main job and importance of the respiratory system is to move fresh air into your body while removing waste gases.

Question 8

Define gas exchange

Answer 8

The process of taking oxygen in and getting carbon dioxide is gas exchange, and takes place in the alveoli of the lungs. Air enters our lungs through the process of breathing. The oxygen in air then needs to enter our bodies in order to get to our cells where it is needed for respiration. The carbon dioxide (a waste product of respiration) also needs to leave our bodies. Carbon dioxide is dangerous to humans in high concentrations so we need to get rid of it from our bodies.

Question 9

Describe the process of breathing

Answer 9

Breathing is the physical process where we inhale air into our lungs and exhale out of our lungs.

Question 10

Explain the difference between respiration and breathing

Answer 10

Respiration is the chemical process where glucose and oxygen undergo a reaction to release energy. While breathing is the physical process where we inhale air into our lungs and exhale out.

Question 11

Describe the effects of smoking on the respiratory system

Answer 11

Smoking damages your airways and the alveoli found in your lungs and can therefore cause lung disease.

Question 12

Identify and describe some long term effects of smoking

Answer 12

Emphysema, Cancer, stroke and heart attack

Question 13

Define the terms: Carcinogenic and Addictive

Answer 13

Carcinogenic: having the potential to cause cancer.

Addictive: a chronic relapse disorder caused by addiction.

Question 14

Name the key structures and functions for the circulatory system

Answer 14

There are 2 loops in the circulatory system. The first goes to and from the heart visiting the lungs to collect oxygen and get rid of carbon dioxide. The other loop is significantly longer and goes to and from the heart but travels all around the body in between.

The heart: it pumps blood around the circulatory system.
The other half of the system: the blood in your system also carries and takes carbon dioxide from your body and delivering it back to the lungs. The waste product is then expelled when exhaled.

Question 15

Describe the importance of the circulatory system

Answer 15

The circulatory system transports blood around the body to deliver oxygen and nutrients to organs, and remove carbon dioxide and waste products from organs.

Question 16

Label a diagram of a mammalian heart to show direction of blood flow

Question 17

Describe how exercise affects the rate of the heart beat

Answer 17

Because your muscles are moving more during exercise, they require more oxygen, therefore your heart beats faster to get more blood pumping.

Question 18

Describe the difference between aerobic and anaerobic respiration

Answer 18

Aerobic:
We inhale air which contains oxygen, and our body digests some of the food to provide glucose. The glucose and oxygen are used in a chemical reaction called respiration. Every cell in our body needs energy to carry out its functions.

Anaerobic:
When there is not enough oxygen, the cells in the body undertake anaerobic respiration.

Question 19

Identify the 3 different types of blood vessels

Answer 19

Arteries, veins and capillaries

Question 20

Compare and contrast the structures and functions of different blood vessels

Answer 20

Arteries: they have thick walls with lots of muscle and elastic and narrow bore (lumen), no valves and appears red when you seen through skin. They carry blood away from the heart and mainly carry oxygenated blood, and need to be strong as they carry blood under high pressure.

Veins: they have thin walls with small amount of muscle and elastic, they have a wide bore (lumen) include valves and appear blue/purple when seen through skin. They carry blood towards the heart and mainly carries deoxygenated blood and needs valves to keep blood moving in the right direction.

Capillaries: they have thing walls (one cell thick) very small bore (lumen) no muscles or elastic in walls and no valves. They deliver oxygenated blood to tissues and take deoxygenated blood away. They need to be thing for gases and nutrients can get in and out easily.

Question 21

Describe the importance of blood

Answer 21

Your blood takes nutrients hormones and oxygen around your body.

Question 22

Identify and describe the functions of the four components of blood

Answer 22

White blood cells: make up 1% of the blood, is the biggest type of blood cell and has a nucleus, they are colourless but can appear light purple/pink and have a round shape. They help to protect the body from infection, can squeeze through small blood vessels to get to invading pathogens, by ingesting then digesting or by producing antitoxins to neutralise the toxins produced by them, or produce antibodies to kill them.

Red blood cells: 45% of the blood, small round cells with indents in the center, no nucleus, thin cells membrane to allow absorption of oxygen. they are red due to the protein that allow them to carry oxygen from lungs to other tissues in your body (hemoglobin) and small so they can pass through small blood vessels. They transport oxygen around the body (have many adaptions to do this). the oxygen absorbed by RBC combine with haemoglobin which combines with oxygen to form oxyhaemoglobin.

Platelets: they are usually round or oval, small colourless fragments in our blood and do not have a nucleus. They form clots (scabs), which stops too much blood being blood and prevents infection.

Plasma: 55% of blood. includes substances such as, carbon dioxide (waste from respiration), waste like urea, and nutrients needed by the body such as glucose. A liquid that carries substances around the body.