B4 Organisation In Animals Flashcards
What are the five levels of organisation living organisms?
Cells, tissues, organs, organ systems, organisms.
What are cells classed as?
The basic building blocks.
What is tissue?
Groups of cells that have similar structures and functions.
What are organs?
Groups of tissues working together to perform a specific function.
What are organ systems?
Groups of organs working together.
What is an organism?
Organ systems work together, forming an organism.
What is the purpose of the pancreas?
To make the enzymes amylase, lipase and protease.
What is the purpose of the liver?
To make bile.
What is the purpose of the gall bladder?
To store bile.
Why do we need bile?
It’s an alkaline that neutralises hydrochloric acid from the stomach, and emulsifies fat to form small droplets with a large surface area.
What is the purpose of the small intestine?
It’s where digested food is absorbed into the blood.
What is the purpose of the large intestine?
It’s where water and minerals are absorbed into the blood.
What is the purpose of the mouth?
It’s where food is chewed.
What is the purpose of the salivary glands?
To make saliva containing the enzyme amylase.
What is the purpose of the oesophagus?
It carries food to the stomach.
What are the purposes of the stomach?
•churns food
•releases protease, digests proteins
•releases hydrochloric acid- kills pathogens
What is the purpose of the rectum?
To store faeces.
What is the purpose of the anus?
To expel faeces.
When breathing in, air moves…
1) into the body through the mouth and nose
2) down the trachea
3) into the bronchi
4) through the bronchioles
5) into the alveoli
6) oxygen then diffuses into the blood in the network of capillaries over the surface of the alveoli
Oxygenated blood goes … of the heart?
Out.
Deoxygenated blood goes … of the heart?
In.
What’s the purpose of red blood cells?
They bind to oxygen and transport it around the body.
What’s the purpose of plasma?
It transports substances and blood cells around the body.
What is the purpose of platelets?
They form blood clots to create barriers to infections.
What is the purpose of white blood cells?
They’re part of the immune system to defend the body against pathogens.
What is the function of an artery?
To carry blood away from the heart (high pressure).
What is the function of a vein?
To carry blood to the heart (low pressure)
What is the function of a capillary?
•carries blood tissues and cells
•connects arteries and veins
What is the structure of an artery?
•thick, muscular, and elastic walls
•the walls can stretch and withstand high pressure
•small lumen
What is the structure of a vein?
•have valves to stop blood flowing the wrong way
•thin walls
•large lumen
What is the structure of a capillary?
•one cell thick- short diffusion distance for substances to move between the blood and tissues
•very narrow lumen
What is the purpose of the heart?
To pump blood around the body.
What type of tissue is the heart made out of?
It’s made from cardiac muscle tissue which is supplied with oxygen by the coronary artery.
What is the purpose of the pulmonary vein?
To take deoxygenated blood to the lungs.
What is the purpose of the vena cava?
It brings deoxygenated blood into the heart.
What is the purpose of the right ventricle?
To pump blood to the lungs.
What controls the heart rate?
A group of cells in the right atrium that generate electrical impulses.
What are artificial pacemakers used for?
Controlling irregular heartbeats.
Why is the human circulatory system described as a ‘double circulatory system’?
Because blood passes through the heart twice for every circuit around the body.
