Topic 2 - Organisation Flashcards
What is a cell?
Cells are the basic building blocks that make up all living organisms.
What is an example of a cell in plants?
Root hair cell.
What is an example of a cell in animals?
Epithelial tissue.
What is a tissue?
A tissue is a group of similar cells that work together to carry out a particular function.
What is an example of a tissue in animals?
Epithelial tissue covers some parts of the body.
Muscular tissue contracts to move whatever its attached to.
Glandular tissue which makes and secretes chemicals like enzymes and hormones.
What is an organ?
An organ is a group of different tissues that work together to perform a particular function.
What is an example of an organ?
The stomach which is made out of muscular tissue, glandular tissue and epithelial tissue.
Muscular tissue moves the stomach to churn up the food.
Glandular tissue which makes digestive juices to digest food.
Epithelial tissue which covers the outside and inside of the stomach.
What is an organ system?
It is a group of organs working together to perform a particular function.
Give an example of an organ system.
The digestive system breaks down and absorbs food. It is made up of; Salivary Glands Pancreas Stomach Small intestine Large intestine Liver
What is the role of each organ in the difestive system?
Pancreas and Salivary Gland-Produces digestive juices
Stomach and Small Intestine-Digests food
Liver-Produces bile
Small Intestine-Absorbs soluble food molecules
Large Intestine-Absorbs water from undigested food
What is a catalyst?
A substance that increases the speed of a reaction without being changed or used up in the reaction.
How do enzymes work?
Every enzyme has an active site with a unique shape that fits onto the substance involved in the reaction.
The substrate complimentary to the enzyme collides creating an enzyme substrate complex.
The substrate breaks down in the active site.
The product is then released so the enzyme can be reused.
How does temprature effect enzymes?
At first the higher temprature increases the rate.
But then when the enzyme passes optimum temprature the bonds holding the enzyme together begins to break which denatures the enzyme.
This means the substrate wont fit into the active site anymore.
How does pH effect enzymes?
If it is too high or too low it changes the shape of the active site and it denatures.
Explain how you investigate how pH effecrs amylase activity.
Put a bunsen burner on a heat proof mat and s tripod and gauze over it. Put a beaker of water over it and heat the water until it is 35 degrees.
Use a syringe and add 1cm cubed of amylase soultion and 1cm cubed of buffer solution with pH 5 to a boiling tube.
Using test tube holders, put the tube into the beaker of water and wait five minutes.
Then add 5cm cubed of starch solution to the boiling tube.
Mix the contents and start a stop clock.
Use continuous sampling and record how long it takes for the amylase to break down the starch.
Take a fresh sample from the boiling tube every 30 seconds and put a drop into a well.
When the iodine solution remains browny orange starch is no longer present.
Repeat the experiment wirh different pH values and see how it effexts the time for starch to be broken down.
How do you calculate the rate of reaction?
Rate = 1000
———
Time
Where is amylase found?
Salivary Glands
Pancreas
Small Intestine
Where is protease found?
Stomach
Pancreas
Small Intestine
Where is lipase found?
Pancreas
Small Intestine
What is the role of bile in the digestive system?
The stomach makes the pH to acidic for the enzymes in the small intestine so bile neutralises the acid because it is an alkaline.
It emulsifies fats which gives a much bigger surface area for lipase meaning faster digestion.
What is the role of hydrochloric acid in the digestive system?
To kill bacteria.
To give the right pH for protease to work.
How do you test for sugars in foods?
Prepare a food sample and put 5cm cubed into a test tube.
Prepare a water bath and set it to 75 degrees.
Add Benedict’s solution (about 10 drops)
Put the test tube into the water bath and leave it there for five minutes.
If the food sample contains a sugar it will go from blue to green, yellow or brick-red depending on how much sugar.
How do you test for starch in food?
Put 5cm cubed of food sample into a test tube.
Add a few drops of iodine solution abd gently shake in the tube.
If the contents contains starch the colour will change from browny-orange to black or dark blue.
How do you test for proteins in food?
Prepare a food sample and put 2cm cubed of your sample in a test tube.
Add 2cm cubed of biuret solution to the sample and mix by gently shaking it.
If it contains protein it should change from blue to pink or purple.
How do you test for lipids in food?
Prepare a sample of food and put around 5cm cubed into a test tube.
Using a pipette add 3 drops of Sudan III solution and gently shake the tube.
If the sample contains lipid the mixture will spearate out into two layers and the top layer will be bright red.
Describe the journey of the heart.
Deoxygenated nlood enters the right atrium via the vena cava.
It the pass through the tricuspid valve and into the right ventricle.
The heart then contracts and pushes the blood out of the right ventricle into the pulmonary artery and transports blood to the lungs.
Oxygenated blood then enters the left atrium via the pulmonary vein.
It then goes through the bicuspid valve and into the left ventricle.
The blood then goes into the aorta and takes oxygenated blood to the muscles and body.
What does the aorta do?
Takes oxygenated blood to the body.
What does the pulmonary vein do?
Takes oxygenated blood to the heart.
What does the pulmonary artery do?
Takes deoxygenated blood to the heart.
What dies the vena cava do?
Takes deoxygenated blood to the heart.
What is plasma?
It makes up 50% of your blood, it contains red blood cells, hormones, and dissolved substances.
What are red blood cells?
Carries oxygen for the lungs to the cells in the body.
It is biconcave to give a large surface area for absorbing oxygen.
The dont have a nucleus which allows for room to carry oxygen.
It also carries harmoglobin which binds to oxygen to form oxyhaemoglobing in the lungs.
In the body the revese happens where the oxygen and haemoglobin split to release oxygen into the cells.
What are white blood cells?
They engulf unwelcome microorganisms in phagocytosis.
They produce antibodies to fight microorganisms and anti toxins to neutralise toxins.
What are platelets?
Small fragments of cells with no nucleus, they help blood to clot around a wound.
How does the structure of arteries help its function?
The heart pumps out blood at high pressure so the walls are strong and elastic.
The walls are thick compared to the lumen.
Thick muscle lauer makes them strong and elastic fibries allows them to stretch and spring back.
How are capillaries structures related to their function?
They have permeable walls so substances can diffuse in and out.
Close to every cell in the body to exchange substances with them.
Wall is only one cell thick so increases rate of diffusion.
They supply food and oxygen and take away waste like carbon dioxide.
How is the structure of a vein related to its function?
Blood comes at a lower pressure so the walls dont have to be as thick.
They have bigger lumen to help blood flow.
They have valves to prevent backflow.
What is the difference between a double and single circulatory system?
One passes the heart twice.
Mammals have double because they need to respire more than smaller animals like fish.
How do you calculate cardiac output?
Heart Rate x Stroke Volume
What is coronary heart disease?
When the coronary arteries get blocked by lauers of fatty material building up.
What are the symptoms of coronary heart disease?
Breathlessness
Fatigue
What are replacement valves?
When a diseased valve is replaced with a new one, it may be mechanical or tissue.
What are the advantages and disadvantages of pacemakers?
They can improve quality of life.
Most common type of heart surgery.
May feel heavy and uncomforable.
What are the advantages and disadvantages of replacement valves?
Strong and durable.
Enables natural flow of blood.
Hear the valves opening and closing.
Have to take anti-clot drugs.
Desribe inspiration.
Ribs pull up and out.
Volume in chest increases.
Diaphragm contracts.
Increased volume decreases the pressure.
Pressure in the chest is less than the atmospheric pressure.
Air moves into the lungs from outside and inflates.
Describe expiration.
Ribcage goes down and in.
Diaphragm relaxes.
Volume in chest decreases.
Decreased volume i creases the pressure.
Pressure in chest is more than the atmospheric pressure.
Air moves from inside the lungs to outside and they flatten.
