Flashcards in Organisation And The Digestive System Deck (100):
The breaking down of large food molecules into smaller water soluble molecules both chemically and physically, occurring in certain organs e.g the pancreas
Why is digestion important?
Large insoluble food molecules cannot get into the blood which need to be used by our cells for vital processes e.g respiration and proteinsynthesis
What is the alimentary canal?
A muscular tube running through the body fork the mouth to anus
What is the function of bile? (3 points)
Breaks down large globules of fat into smaller ones (emulsifies them), increases the surface area of fat droplets, neutralises hydrochloric acid from the stomach as it’s alkaline
What concentration of oxygen does blood going into the stomach have?
What concentration of oxygen do cells lining the stomach have?
By which process does oxygen move from the blood to the cells lining the stomach?
What other substance moves from the blood to the cells lining the stomach so that respiration can take place?
In which part of a cell does aerobic respiration take place?
How many alveoli does a human lung have?
About 80 million
Give three features of the alveoli which allow large amount of oxygen to enter the blood
Large surface area, lots of capillaries, thin walls
Name the process by which oxygen passes from the air into the blood
How does breathing allow large amounts of oxygen to enter the blood?
More oxygen enters the alveoli and carbon dioxide passes out into the air, the alveoli maintains a higher concentration of oxygen
How are the villi adapted to maximise the rate of absorption of the products of digestion? (3 ways)
Lots of microvilli provides a large surface area, lots of capillaries meaning they maintain concentration gradient, they have lots of mitochondria which allows for respiration and energy release
Function of the small intestine?
digestion of fat
Function of the large intestine?
absorption of water into the blood
Function of the stomach?
Production of hydrochloric acid
How does the glucose concentration in the blood compare to that of the small intestine?
The concentration in the blood is lower
Which three organs produce amylase?
Salivary glands, pancreas, small intestine
Which two organs produce lipase?
Pancreas, small intestine
Which two organs produce protease?
How does acid help digestion?
This is the optimum pH for the enzymes
Amylase breaks down starch into...
Lipase breaks down fats into...
Fatty acids and glycerol
Protease breaks down proteins into...
Where is bile produced and released into?
Produced in the liver, released into the small intestine
Optimum pH of amylase?
optimum pH of protease?
Optimum pH of lipase?
Function of the rectum?
Function of the salivary glands?
Produces saliva containing the enzyme amylase
Function of the mouth?
What is the oesophagus?
A tube connecting the mouth to the stomach
Function of the anus?
Faeces leaves the body here
Function of the pancreas?
Produce enzymes and release them into the small intestine
Function of the gall bladder?
Function of the liver?
Oxygen moves from the lungs into the blood through the walls of what?
Two adaptions of the lungs that help rapid absorption of oxygen into the blood?
Large surface area, thin membrane
How do you test for sugar and what colour change will occur if sugar is present?
Benedicts reagent, green to orange to brick red
How do you test for starch and what colour change will occur?
Iodine, Brown to blue black
What is the function of enzymes?
Break down large insoluble food molecules into small soluble ones so they can diffuse into our cells
What are enzymes?
Biological catalysts, they are made of protein
The sum of all reactions in a cell or in the body
Why are digestive enzymes different?
Work outside of your cells, are released from specialised cells in glands and the lining of the gut, secreted onto the food travelling through the digestive system
What happens in an enzyme reaction if the temperature/pH is too high/strong?
The active site becomes denatured therefore the are less collisions so the reaction decreases and stops
How do we test for fat and what colour change occurs?
Reagent is filter paper, turns clear
How do we test for protein and what colour change occurs?
Reagent is Biuret, turns slightly pink
Why do enzymes have an optimum temperature?
They work best at this temperature and enzyme-substrate complexes form more quickly
Function of the heart?
To pump blood around the body
In which direction does an artery pump blood?
Away from the heart
In what direction does a vein pump blood?
Into the heart
Function of the veins?
To carry blood from the capillaries back to the heart and lungs
Function of skeletal muscles?
To push the blood up the body and back to heart
Is the blood carried by the veins oxygenated or deoxygenated?
Function of the arteries?
Carry blood away from the heart and to body cells
What pressure do veins carry blood under?
What pressure do arteries carry blood under?
What is the lumen lined with?
Is the blood carried by the arteries oxygenated or deoxygenated?
Function of the capillaries?
Carry blood away from the body and exchange nutrients, waste and oxygen with tissues at the cellular level
What do the capillaries’ tiny blood vessels do?
Is the blood carried by the capillaries oxygenated or deoxygenated?
What are platelets?
Cell fragments essential to blood clotting
Function of white blood cells?
Protect the body against disease
Function of the red blood cells?
Transport oxygen and have no nucleus to make more room
What is cardiac output?
The amount of blood the heart pumps in a minute
What is heart rate?
How often the heart beats
What is stroke volume?
How much blood is pumped out of the heart with each beat
What is the relationship between those three things?
CO = HR x SV
Four features of a good exchange surface?
Thin walls, good ventilation, lots of capillaries, large surface area
What is ventilation?
The process of inspiration and expiration
What happens during inspiration?(7 parts)
Ribs pull up and out, volume in chest increases, diaphragm contracts, further volume increase inside the chest, lower pressure in chest (less than atmospheric pressure), air drawn into the lungs from outside, lungs deflate
What happens during expiration? (6 parts)
Ribs pulled down and in, volume in thorax decreases, decrease in chest volume, pressure greater than atmospheric pressure, air forged out of lungs, lungs deflate
What is the relationship between pressure and volume?
Low pressure = high volume
What is health?
A state of physical and mental well-being
What is a risk factor?
Any factor, attribute, characteristic that increases the risk of developing a disease
What is a correlation?
A change in one variable is reflected by a change in another variable
What is cancer?
A group of diseases involving cells in a specific part of the body growing and reproducing uncontrollably
How does a tumour form?
Sometimes damaged cells pass through checkpoints which allows them to divide
4 characteristics of a benign tumour?
Not cancerous, cannot spread, inside a membrane, cause damage to other organs
6 characteristics of a malignant tumour?
Cancerous, can spread, can invade healthy tissue, cells can travel in the blood or lymph system, can form secondary tumours in other organs, destroys organs
What is the name for cell division?
4 risk factors of lung cancer?
Smoking, lack of exercise, unhealthy diet, air pollution
Risk factor of skin cancer?
Exposure to UV radiation
4 risk factors of cervical cancer?
Obesity, multiple pregnancies, smoking, STIs
3 risk factors of breast cancer?
Inherited genes, lack of exercise, unhealthy diet
4 risk factors of testicular cancer?
Smoking, unsafe sex, STIs, infertility
4 risk factors of brain tumours?
Radiation, smoking, drinking, being overweight
What is coronary heart disease?
Narrows the arteries which reduces the amount of blood travelling through them and reduces the amount of it reaching the heart so heart cells die
What happens with a faulty heart valve?
Pressure cannot build up in the chambers, heart must work harder to build up enough pressure, blood may back flow or clot
What do statins do?
Reduce cholesterol and build up of fat
What do stents do?
Allow blood to flow mor freely by holding coronary arteries open
What is a communicable disease?
An infectious disease transmissible by direct or indirect contact with an affected individual or their discharges
What is a non communicable disease?
A disease which is non infectious and non transmissible among people
6 ways disease is spread?
Water&food, animals, insects, bodily fluids, the aid, direct contact
8 ways to decrease your risk of disease?
Get vaccinated, wash hands often, use antibiotics safely, disinfect hot zones in your residence, don’t share personal items, travel wisely, safe sex, be smart about food prep
What is phagocytosis?
The process by which a cell (often a phagocyte or protist) engulfs a solid particle to form an internal compartment (a phagosome)
What is a phagocyte?
A type of cell within the body capable of engulfing and absorbing bacteria and other small cells and particles