(ORGANISATION) Animal Tissues, Organs and Systems Flashcards
What is the main function of the digestive system?
To digest food and absorb the nutrients obtained from digestion
What is the role of the pancreas and the salivary gland in the digestive system?
The pancreas and the salivary gland are glands which produce digestive juices containing enzymes.
What is the role of the stomach in the digestive system?
Produces hydrochloric acid which kills bacteria present and provides optimum acidic pH for the protease enzyme to function
What is the role of the small intestine?
The site where soluble food molecules are absorbs into the blood stream
What is the role of the liver?
Produces bile (stored in the gallblader) which emulsifies lipids and allows the lipase enzyme to work more efficiently
What is the role of the large intestine?
Absorbs water from undigested food, producing faeces (poop)
What is the role of enzymes?
They act as a biological catalyst which speeds up the rate of reactions without being used up
What is the ‘lock and key’ hypothesis of enzyme function
The shape of the enzyme active site and the substrate are complementary, so can bind together to form an enzyme-substrate complex
Where are the carbohydrates, proteases and lipases produced in the body?
- Carbs; amylase = salivary gland
- Proteases; pepsin = stomach
Lipases; pancreas and small intestine
What is the role of proteases in the digestive system?
To break down proteins into amino acids
What is the role of lipases
They break down lipids into fatty acids and glycerol
What is the roll of bile?
- Is an alkaline substance which neutralises the hydrochloric acid secreted by the stomach
- Bile emulsifies lipids to form droplets - this increases the surface area for the lipase enzyme to work on
Where does blood pumped from the right ventricle go?
lungs
Where does blood pumped from the left ventricle go?
body tissues
How many chambers does the heart have?
4
- Right/Left Atrium
- Right/Left Ventricle
Why is the wall of the left ventricle thicker?
Has to pump blood at a higher pressure around the whole body
What are the main 5 blood vessels?
- Aorta (carries oxygenated blood from heart to body
- Pulmonary vein (carries oxygenated blood from lungs to heart)
- Vena Cava (carries deoxygenated blood from the body to heart)
- Pulmonary artery (carries deoxygenated blood from the heart to lungs)
What is the purpose of valves?
Prevent backflow of blood
What is the purpose of coronary arteries?
They supply the heart muscle with oxygenated blood
How is the heart rate controlled?
By a group of cells in the right atrium which acts as a pacemaker. They release waves of electrical activity which cause the heart muscle to contract
What are the 3 blood vessels?
- Arteries
- Veins
- Capillaries
How are arteries adapted to their function?
Function = carry blood AWAY from heart
Thick muscle layer which adds strength to resist high pressure and a thick elastic layer which allowed arteries to stretch and recoil
How are veins adapted to their function?
Function = carry blood TO the heart
Wide lumen which enables low pressure and valves to prevent backflow
How are capillaries adapted to their function?
Function = enable transfer of substances between blood and tissues
Walls are one cell thick which is a short diffusion path. Permeable walls mean that substances can diffuse across and the narrow lumen makes the blood flow slowly (more time for diffusion
What substance carries the different components of blood?
Plasma
What substances are transported by plasma?
Red/White blood cells
Platelets
CO2
Urea
Products of digestion
What is plasma?
A yellow liquid within blood that transports substances around the body
Purpose of red blood cells?
Transport oxygen around the body
How are RBC adapted to their function?
Biconcave shape - increased surface area to volume ratio
No Nucleus - more room for haemoglobin
Contains haemoglobin which binds to oxygen
Purpose of WBC?
They form part of the immune system which protects the body from invading pathogens
What is coronary heart disease?
CHD occurs when the coronary arteries that supply the heart muscle become blocked with the build up of fatty material. This restricts the supply of oxygen to the heart, possibly leading to a heart attack or death
What is a stent and how does it work
A stent is a metal mesh tube that is inserted into a blocked artery so that it remains open. The stent is inflated using a balloon, which is later removed to allow blood to flow freely
How can diet affect health?
Too little food / lack of nutrition = anaemia, vitamin deficiencies.
Too much food / too much unhealthy food = obesity, type 2 diabetes
What is a benign tumour
- A tumour that is contained in one location, usually within a membrane.
- They’re not cancerous and do not invade other parts of the body
- Can grow large quickly which may cause damage to another organ
What isa malignant tumour?
- A tumour that can spread around the body via the blood and lymphatic system.
- Can invade other tissues
- Cells divide more rapidly and have a longer lifespan
- Disrupts healthy tissues and may lead to death
