Human Systems
Digestive System
Parts: Mouth, Gullet, Stomach, Small Intestine
,Large Intestine, Rectum and Anus.
Chemical Digestion:
Breaks food down into simpler substances by adding chemicals to it.
Mechanical Digestion:
Breaks food into smaller pieces by actions such as grinding, biting and chewing.
Function of system:
To digest (Break down food into smaller parts and simpler substances) to be absorbed into the body.
Functions of parts:
Mouth: Mechanical and Chemical Digestion takes place here. Mechanical Digestion takes place when the food is chewed by the teeth. Chemical Digestion takes place when saliva is added to the food.
Gullet: A tube that the food travels down towards the stomach. Saliva added to the food continues to act on the food in the gullet.
Stomach: Churning that involves Mechanical and Chemical Digestion takes place here. Mechanical Digestion takes place when the stomach expands and contracts to bounce the food around the stomach. Chemical Digestion takes place when digestive juices in the stomach act on the food.
Small Intestine: The Small Intestine is about 6.9 metres long in an adult male an about 7.1 metres long in an adult female. It has three parts: The Duodenum, The Jejunum and the Ileum. The food (Now called a thick soup or chyme) has bile from the gallbladder and panreatic juice from the pancreas to the chyme.The Duodenum is 20-25 cm long and is shaped like a C. In the Jejunum, small folds called villi and microvilli absorb fatty acids, sugars and amino acids from the chyme into the bloodstream.The Jejunum is about 2.5 m long. In the Ileum, other nutrients are absorbed into the bloodstream via villi and microvilli, the Ileum is about 3m long.
Large Intestine: The large intestine absorbs the water from the undigested food. It is 1.5m long.
Rectum: Undigested food travels here before being passed out by the Anus.
Muscular system
Parts:muscles
Function of system:
Make body move
Function of parts:
Muscles: Make the body move
Skeletal system
Parts: Bones
Function of system:
Keep body upright and give body shape
Function of parts:
Bones: Keep the body upright and give body shape. Bone Marrow produces new blood cells.
Respiratory System
Parts: Nose, windpipe, lungs.
Function of system:
Help body take in air and carry out gaseous exchange
Functions of parts:
Nose: Takes in air, air taken in through nose is filtered by nose hairs and mucus, warmed and moistened. If you have a blocked nose, your mouth can still take in air, but that air taken in through the mouth is not warmed, moistened or filtered.
Windpipe: A pipe that air travels down, it has tiny hairs inside it that filter air. It consists of a long tube called the trachea,which branches into two tubes called the bronchus, which each branch into bronchioles inside the lungs.
Lungs: Carry out gaseous exchange, it is protected by thoratic cavity and the ribcage. When breathing in, the thoratic cavity expands and the diaphragm, an organ below the lungs moves down. When breathing out, the thoratic cavity returns to its original volume and the diaphragm moves back into its original position. There are tiny air sacks called alveoli at the end of the bronchioles that are surrounded by capillaries, the oxygen moves into the bloodstream through the air sacs and carbon dioxide exits the bloodstream via the air sacs.
Circulatory system
Parts: Blood Vessels and Heart. Blood Vessels let blood flow through them,heart pumps the blood around the body.
Different components of blood:
Red Blood Cells: Cells with no nucleus, they chuck their innards out when created to make space for hemoglobin, which helps them to carry gases around the body. These have a life span of 120 days! Consist of 40-45% of blood
White Blood Cells: Fight germs and viruses in the bloodstream. Have an extremely short lifespan of 18-36 hours. Have a few types.
Platelets: Helps blood to clot
Plasma: Contains nutrients. 90% of it is water.
Blood cells and platelets make up 40-45% of blood and the remaining 55% of it is plasma. All blood cells start out as stem cells.
Function of system:
Circulate blood around the body
Functions of parts:
Capillaries: Thin-walled blood vessels , red blood cells must flow in single file to pass through. Allows gas exchange between blood vessels and cells.
Arteries: Thick- walled blood vessels, Carries oxygenated blood
Veins: Thin- walled blood vessels, carries deoxygenated blood.
Heart:Pumps at an average 72 beats a minute. Consists of 4 chambers which are the left atrium,left ventricle,right atrium and right ventricle.
Right Ventricle and Right Atrium
Pumps Deoxygenated Blood to the lungs.
Left Ventricle and Left Atrium
Pumps Oxegenated blood to all parts of the body
Oxegenated blood enters left atrium through pulmonary veins.
