Topic 2 - Organisation Flashcards
What is the order of how cells become organ systems?
Cells - Tissues - Organs - Organ systems
What is a catalyst?
Catalyst:
— A substance which increases the speed of a reaction without being changed or used up in the reaction.
What is an enzyme?
Enzyme:
— A biological catalyst
How does an enzyme work?
Hint: what needs to fit into what for it to work
Each enzyme has an unique active site that only allows a certain substrate to fit into it. Think of it as the ‘lock and key’ diagram. For the enzyme to work, the substrate has to fit into the active site.
What is the general optimum temperature and pH that enzymes work best at?
What happens if the optimum conditions are not met?
- – The optimum temperature is 37 degrees and the optimum pH is 7 (neutral).
- – If the temperature gets too hot or pH is too low or too high, then the enzyme can denature. This means that the shape of the active site could change which means the substrate won’t be able to fit into the active site anymore meaning the enzyme won’t work.
What big molecules do carbohydrases (e.g. amylase), proteases and lipases break down into smaller molecules?
- – Carbohydrases break down cabohydrates into simple sugars (e.g. amylase breaks down starch to maltose)
- – Proteases break down proteins to amino acids
- – Lipases breaks down lipids into glycerol and fatty acids
Where are carbohydrases, proteases and lipases found in the body?
- – Carbohydrases: salivary glands, pancreas, small intestine
- – Proteases: pancreas, stomach, small intestine
- – Lipases: pancreas, small intestine
Where is bile produced and stored? What is the role of bile in the body?
Bile is produced in the liver and stored in the gall bladder. The role of bile is to emulsify fats and neutralise stomach acid. The bile breaks the fats into tiny droplets to increase the surface area for the lipases to act on. Also it neutralises stomach acid because the pH of the stomach is 2 which is very acidic so because bile is alkaline, it neutalises the acidic conditions.
What side of the heart pumps oxygenated blood and which side pumps deoxygenated blood?
- – Right side: deoxygenated blood
- – Left side: oxygenated blood
What do valves do?
Valves prevent backflow of blood in the heart.
What are the four chambers of the heart?
Right atrium, right ventricle, left atrium, left ventricle
How does the heart pump blood around the body?
Dexoygenated blood flows into the right atrium via the vena cava. The right atrium contracts forcing the blood into the right ventricle which then contracts to force the blood into the pulmonary artery away from the heart and into the lungs where gaseous exchange takes place. The oxygenated blood then enters the left atrium via the pulmonary vein. The left atrium contracts, forcing blood into the left ventricle which then contracts and forces blood out of the heart and to the rest of the body via the aorta.
What is the role of a pacemaker and where is it located in the heart?
A pacemaker is a group of cells that control the natural resting heart rate of a person. It is located in the right atrium of the heart. An artificial pacemaker can be used to control an irregular heartbeat.
What are the three blood vessels and their functions?
- – Arteries: carry blood away from the heart under a lot of pressure
- – Capillaries: involved in exchanging material at the tissues
- – Veins: carry blood to the heart
How does the structure of each blood vessel relate to its function?
- – Arteries: have thick walls that are very strong and elastic as they work under high pressure, the lumen is not very big
- – Capillaries: thin permeable walls that are one cell thick to increase the rate of diffusion of substances and very small lumen
- – Veins: thin walls as they work under low pressure, wide lumen to allow blood to flow under the low pressure, contain valves to prevent backflow of blood
What are the main components in blood and their functions?
- – Red blood cells: carry oxygen
- – White blood cells: prevent against infection
- – Platelets: help blood clot
- – Plasma: liquid that carries everything in the blood
How are the components of the blood adapted to perform their functions?
- – Red blood cells: biconcave shape for an increased surface area to carry more oxygen, no nucleus provides more room to carry oxygen, red pigment called haemoglobin which binds to oxygen in the lungs to transfer more oxygen around the body
- – White blood cells: changes shape to engulf and digest microorganims (phagocytosis), produces antibodies and antitoxins to counteract the effect of harmful toxins in microorganisms, contains a nucleus.
- – Platelets: small fragments of cells with no nucleus, help blood clot at a wound to prevent excessive bleeding and prevent harmful microorganisms enter the body
- – Plasma: pale straw-coloured liquid that carries RBC, WBC, platelets, nutrients, carbon dioxide, hormones, urea, antibodies and antitoxins
What causes coronary heart disease?
When layers of fatty material build up in the coronary ateries which narrow them causing a reduced flow of blood so a lack of oxygen for the heart muscle.
How do stents and statins help people with coronary heart disease?
Stents help by keeping the coronary artery open. Statins reduce the amount of bad cholesterol in the blood which reduces the amount of fatty deposits forming in the coronary arteries.
What is the effect of faulty heart valves and how can they be replaced?
A faulty valve means a valve cannot open or might leak which will allow blood to flow in both directions. It can be replaced using a biological or mechanical valve.
What could happen in the event of heart failure?
- – An articifcial heart can be implanted to help pump blood around the body while waiting for a transplant or give the heart a break from pumping to aid its recovery
- – Heart transplant (maybe lung too if needed)
What are risks and benefits of an artificial heart?
Benefit:
— Less likely to be rejected as it is not seen as ‘foreign’
Risks:
- – Can cause bleeding or infection
- – Wears out or electrical motor could fail
- – Patient has to take drugs to thin the blood to prevent blood clots
What is health?
Health is the state of physical and mental well-being.
What are four examples of when diseases can interact with each other?
- – A weak immune system makes it harder for the body to fight infectious diseases and give a higher chance of catching communicable diseases.
- – Viruses living in cells can trigger cancers.
- – Immune system reactions caused by pathogens can trigger allergies such as skin rashes or asthma.
- – Severe physical illnesses can lead to depression and other mental health conditions.
