The digestive system and heart and blood vessels Flashcards
What is a tissue?
A group of cells with a similar structure and function.
What is an organ?
Group of different tissues that work together to perform a certain function.
What are cells
make up all living things
What is an organ system?
A group of organs working together to perform a particular function.
What three main nutrients do food contain?
Carbohydrates, (starch) protein and lipids (fats)
Can carbohydrates proteins and lipids be absorbed into bloodstream?
No because they are large molecules that cannot be absorbed into the bloodstream/can only be digested.
How is food digested?
Large food molecules are broken down into smaller molecules and absorbed into the blood stream.
How does the digestive system work?
Food is chewed in mouth
enzymes in saliva digest starch into smaller sugar molecules.
Food passes down oesophagus and into stomach. Enzyme begin digestion of protein in stomach.
Stomach contain hydrochloric acid/helps enzymes digest protein.
Churning action of stomach muscles turns food into fluid increasing surface area for enzymes to digest.
Fluid passes into small intestine.
Chemicals released in small intestine from liver + pancreas.
Pancreases releases enzymes which continue digestion of starch and protein and start digestion of lipids.
Liver releases bile to speed digestion of lipids.
neutralises acid released from stomach.
walls of small intestine releases enzymes to continue digestion of protein and lipids
The small food small molecules produced by digestion is absorbed into blood stream by diffusion or active transport.
Fluid moves to large intestine where water is absorbed into blood stream
faeces released from body
What is the overview of the digestive system?
Large food molecules are digested into smaller molecules and then products of digestion are absorbed into bloodstream.
Products of digestion are used to build new carbohydrates, proteins and lipids.
Some of glucose produced is used for respiration.
What is the heart?
A organ consisting of mainly muscle tissue.
What is the job of the heart?
To pump blood around the body.
what are the four chambers of the heart?
right ventricle
left ventricle
right atrium
left atrium
What are valves ?
prevent back flow of blood
What are the 4 main blood vessels?
Vena cava
pulmonary artery
pulmonary vein
aorta.
How does the circulatory system work?
Vena cava brings in deoxygenated blood from body.
blood passes from heart to lungs in pulmonary artery.
In lungs blood collects oxygen.
Oxygenated blood passes from lungs to heart in pulmonary vein.
oxygenated blood pumped from heart to body in aorta.
