Organisation Flashcards
What are the 5 levels of organisation in living organisms?
Cells, tissues, organs, organ systems, organisms.
What are cells?
The basic building blocks of all living organisms.
What are tissues?
Groups of cells with 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 are organisms?
Organ systems working together.
What are examples of tissues in plants and animals?
Epidermal and epithelial.
What is another example of an animal tissue?
Muscular.
What is another example of a plant tissue?
Mesophyll.
What structures in the body are involved in the digestive system?
Pancreas, mouth, liver, gall bladder, small intestine, large intestine, stomach, oesophagus, salivary glands, rectum and anus.
What does the pancreas do?
Makes enzymes - amylase, lipase and protease.
What does the mouth do?
Chews food.
What do the salivary glands do?
Makes saliva containing amylase.
What does the oesophagus do?
Carries food to the stomach.
What does the liver do?
Makes bile.
What does the gall bladder do?
Stores bile.
What does the stomach do?
- Churns food.
- Releases protease, digests proteins.
- Releases hydrochloric acid = kills pathogens.
What does the small intestine do?
Where digested food is absorbed into the blood.
What does the large intestine do?
Where minerals and water are absorbed into the blood.
What does the rectum do?
Stores faeces.
What does the anus do?
Expels faeces.
What are the main types of blood vessels?
Arteries, capillaries, veins.
What is the functions of arteries?
- Carries blood away from the heart.
- High pressure.
What is the structure of arteries?
- Thick, muscular and elastic walls.
- The walls can stretch and withstand high pressure.
- Small lumen.
What is the functions of veins?
- Carries blood to the heart.
- Low pressure.
What is the structure of veins?
- Have valves to stop blood flowing the wrong way.
- Thin walls.
- Large lumen.
What is the function of capillaries?
It carries blood to tissues and cells and connects arteries and veins.
What is the structure of capillaries?
- One cell thick.
- Very narrow lumen.
What cells are blood made up of?
Red blood cells, plasma, platelets, white blood cells.
What do red blood cells do?
Bind to oxygen and transport it around the body.
What do plasma cells do?
Transport substances and blood cells around the body.
What do platelets do?
Form blood clots to create barriers to infections.
What do white blood cells do?
Part of the immune system to defend the body against pathogens.
What do arteries carry?
Oxygenated blood.
What does the heart do?
Pump blood around the body.
What is the heart made from?
Cardiac muscle tissue.
What are the structures of the heart?
The pulmonary artery, aorta, vena cava, pulmonary vein, left atrium, right atrium, right ventricle, left ventricle.
What does the pulmonary artery do?
Takes deoxygenated blood to the lungs.
What does the aorta do?
Carries oxygenated blood around the body.
What does the vena cava do?
Brings deoxygenated blood into the heart.
What does the pulmonary vein do?
Brings oxygenated blood from the lungs.
What does the right ventricle do?
Pumps blood to the lungs where gas exchange takes place.
What does the left ventricle do?
Pumps blood around the body.
What is heart rate controlled by?
A group of cells in the right atrium that generate electrical impulses, acting as a pacemaker.
What do artificial pacemakers do?
Used to control irregular heartbeats.
Why is the human circulatory system describes as a double circulatory system?
Because blood passes through the heart twice for every circuit around the body.
