Human body and food tests Flashcards
What drug makes smoking very addictive?
Nicotine.
What can nicotine do that affects your human body?
It stain teeth
It can also harm your heart and narrows blood vessels.
This would eventually lead to heart attacks and strokes
What is tar?
Tar is a dark brown sticky substance which collects in the lungs as the smoke cools.
What is a carcinogen?
Carcinogens are substances that may increase your risk of cancer.
Where can tar be breathed into?
Throat
larynx
trachea
What are proteins made up from?
Amino acids
What are carbs made from?
Units of sugar.
How to prepare a food sample?
1Get a piece of food and break it up using a pestle and mortar
2 Transfer the ground up food to a beaker and add some distilled water
3 Give the mixture a good stir with a glass rod to dissolve some of the food.
4 Filter the solution using a filter funnel
What do you use to test for reducing sugars?
Benedicts solution
Method for testing for proteins
1Prepare a sample of your food and transfer 2cm cubed to a test tube.
2 Add 2 cm cubed of Buirert solution(sodium hydroxide+copper sulfate) to the sample and mix the content of the fuse by shaking it.
3 If the food sample contains protein the solution will change from BLUE to PINK or PURPLE.
Benedicts test?
1 Prepare a food sample and transfer 5 cm cubed to test tube
2 Prepare a water bath so it is set to 75 degrees celsius
3 Add some benedicts solution to the tube (about 10 drops)
4 Place the test tube in water bath using a test tube holder and leave for 5 minutes
5 If the food sample turns from normal blue to green yellow and then brick red it contains carbs
Test for Starch
1 Add a few drops of Iodine solution to the food stuff
2 If the iodine solution turns from orange/red to BLUE/BLACK starch is present
Test for lipids
1 To the test food(dont need to filter) sample and a few cm cubed of sudanIII
2The SudanIII solution will stain any fat/lipid present in the food
3 After shaking the oil floats to the top and stains red to show the Sudan III solution
Name three carcinogens
Tar
Alchohol
Ionising radiation
Muscle?
This contracts and relaxes to break down food.
Epidermal?
This lines the stomach protecting the acid from damaging it.
Glandular?
This releases the enzymes and acid which break down the food we eat.
Explain why people who exercise regularly are usually healthier than people who dont.
People who exercise regularly are usually healthier than people who take little exercise because people who take regular exercise make bigger muscles up to 40% of their body mass, and muscle tissue needs more energy to be transferred from food than body fat.They also have fitter hearts and bigger lungs.
How are exercise and obesity levels linked?
Exercise levels and obesity leves are often linked because the more you exercise the more calories you burn .The less you exercise the less calories you will burn which makes you more likely to be obese.
What is a depressant?
A depressant slows down messages in the nervous system, which includes the brain, spinal cord and other nerves.
What are examples of despressants?
Canabis
Alcohol
What is a stimulant?
Stimulants speed up messages in the nervous system. This makes you feel more alert and shortens reaction times.
What are examples of stimulants?
Cocaine and ecstasy are illegal stimulants
Caffeine is a legal stimulant.
What is the function of the mouth?
The mouth is the beginning of the digestive system and it chews food.
What are the chemicals produced in the mouth?
Glands in your mouth secrete saliva(contains the enzyme AMYLASE)
What is the function of Oesophagus?
The oesophagus carries food to the stomach.Muscular tube.
What are the chemical proccesses that take place in the oesophagus?
Food is pushed through a series of contractions called a peristalsis.
What is the function of the stomach?
Muscular walls of the stomach contract to churn the food breaking it.
What chemical is produced in the stomach?
The stomachcontains hydrochloric acid which kills ingested bacteria.
What is the function of the liver?
It processes absorbed food and detoxifies the blood.
What are the chemicals produced in the liver?
It makes bile which emulsifies fat to form droplets which increases the surface area.
What is the function of the gall bladder?
The gall bladder stores excess bile before it is released into the small intestine.
What chemicals are predocued in the gall bladder?
Bile(alkaline substance)
What is the function of the pancreas?
The pamcreas produce enzymes break down proteins,fats and carbs
What chemical are produced in the pancreas?
Enzymed which break down proteins,fats, and carbs
Lipase
Protease
Carbohydrase
What is the function of the small intestine?
Soluble products of digestion are absorbed into the blood through the vili covered walls.
What chemicals are produced in the small intestine?
The small intesgtine produces protease,amalyse and lipase.
What is the function of the large intestine?
The large intestine connects the small intestine to the rectum.Processes waste.
What chemicals process takes place in the large intestine?
As stool passes through the large intestine water is absorbed.
Rectum and Anus function?
The rectum is an eight inch chamber that connect the colon to the anus.
What is the chemical process in the rectum and anus?
Recieves stool from large intestine.Anus last part of the digestive tract.
What are the three types of tissue the stomach contains?
Muscle
Epidermal
Glandular
What is a catalyst?
People use special chemicals known as catalysts to speed up reactions.
What are enzymes?
Enzymes are special biological catalysts that speed up reactions.Each enzyme reacts with a particular substance.
What are enzymes made of?
Long chain of amino acids
How do enzymes help speed up reactions in your body?
The lock and key theory is a model of how enzymes work.The substrate of the reaction to be catalysed fits into the active site of the enzyme and substrate bind together.The reaction then takes place rapidly and the products are released from the surface of the enzyme.The active site has a complementary shape to substrate.
What carries red blood cells,white blood cells and platelets suspended in it?
Plasma
Red blood cells function?
Transport oxygen.
White blood cells
Protect against disease.
Blood platelets
Help the blood to clot and repair a cut.
What are the three types of blood vessels?
Arteries
Veins
Capilleries
Artery function
Carry blood away from the heart (usually oxygenated blood, except for the pulmonary artery)
Vein function
Carry blood towards the heart (usually deoxygenated blood, except for the pulmonary vein)
Capilleries function?
Allows diffusion of gases and nutrients from blood into the body cells
What size walls do arteries have?
Thick,muscular
Small lumen
What size walls do veins have?
Thinner
Large lumen
What size walls do capillaries have?
Very thin, one cell thick
Very small lumen aswell
How does the heart work?
1)Deoxygenated blood enters the right atrium from the vena cava.
2)Blood moves into right ventricle.
3)Blood is pumped into the pulmonary artery.
4)The pulmonary artery carries deoxygenated blood to the lungs.
5)The blood becomes oxygenated in the lungs.
6)Oxygenated blood leaves the lung via the pulmonary vein.
7)Blood enters the left atrium.
8)Blood moves into the left ventricle.
9)Blood is pumped into the aorta, which carries oxygenated blood around the body.
The heart
Is an unconditional pump
Valves
Are present to prevent the backflow of blood.
The right side pumps..
Deoxygenated blood (low in oxygen and high in carbon dioxide) to the lungs.
The left side pumps…
Oxygenated blood(high in oxygen and low in carbon dioxide) to the lungs
Which ventricle wall is thicker left or right?
Left because it pumps blood around the body whereas the right only pumps blood to the lungs.
Vena cava
Carries deoxygenated blood from the body back to the heart.
Pulmonary artery
Carries deoxygenated blood from the heart to the lungs.
Pulmonary vein
Carries oxygenated blood from the lungs to the heart.
Aorta
Carries oxygenated blood from the heart around the body.
What is the difference between anaerobic and aerobic respiration?
Anaerobic respiration occurs without oxygen and releases less energy but more quickly than aerobic respiration.
What is respiration?
Respiration is a chemical reaction which takes place in all livings cells and releases energy from glucose.
Where does aerobic respiration occur?
Aerobic respiration occurs in mitochondria which are found in the cytoplasm.
What is the equation for aerobic respiration?
(glucose + oxygen -> carbon dioxide + water).
What is the equation for anaerobic respiration?
(Glucose -> Lactic acid).
What is the equation for photosynthesis?
Carbon dioxide + water + (light energy) glucose + oxygen gas.
What is a exothermic reaction?
a chemical reaction that releases energy by light or heat.
What is an endothermic reaction?
any chemical reaction that absorbs heat from its environment.
What is the correct equation for fermentation?
Glucose -> ethanol + carbon dioxide.
In humans, what is true of anaerobic respiration compared with aerobic?
It releases less energy faster.
What is the difference between aerobic and anaerobic respiration?
Aerobic respiration occurs with oxygen and releases more energy but more slowly. Anaerobic respiration occurs without oxygen and releases less energy but more quickly.
What is fermentation?
Fermentation is a metabolic process that allows cells to generate energy in the absence of oxygen.
