Body Systems

Building blocks of all living things, made up of organelle
Multi cellular
More than one cell
Uni cellular
One cell
6 Requirements for a cell to function
Energy, nutrients, water, oxygen, vitamins & minerals and optimum conditions
Intercostal muscles contract, expanding the ribcage, the diaphragm contracts, pulling downwards to increase the volume of the chest
Intercostal muscles relax, the ribcage drops inwards & down, diaphragm relaxes, moving back upwards, decreasing volume of the chest, pressure inside the chest increases and is forced out
Aerobic Cellular Respiration (Formula)
Oxygen + Glucose -> Carbon Dioxide + Water + Energy
Aerobic Cellular Respiration
Cellular respiration is the process by which cells get their energy in the form of ATP
Lungs (Respiratory System)
Spongy, air-filled organs on either side of the chest, containing the bronchi, bronchioles and the alveoli
Respiratory System
Responsible for getting oxygen into your body and carbon dioxide out
Trachea (Respiratory System)
Also known as the windpipe, conducts inhaled air into the lungs through its tubular branches called bronchi
Bronchi (Respiratory System)
Branching off from the trachea, makes passage of airway in the respiratory system that conducts air into the lungs
Bronchioles (Respiratory System)
Smaller branches of the bronchi which contain the alveoli
Alveoli (Respiratory System)
Found inside the bronchioles, where gas exchange occurs
Alveoli Structure
Tiny balloon shaped structure, 1 cell thick, 600 million in the lungs, total surface area of 75m
Circulatory System
Responsible for transporting oxygen and nutrients to body cells and waste (eg. co2) away from cells
3 Main Types of Blood Vessels
Arteries, Capillaries, Veins
Arteries (Circulatory System)
Transports blood AWAY from the heart
Veins (Circulatory System)
Transports blood BACK to the heart
Capillaries (Circulatory System)
Where the materials are exchanged within cells
Heart (Circulatory System)
Muscular organ that pumps body through the blood vessels
Heart Structure
2 sides- left and right- and 4 chambers- left atrium, right atrium, left ventricle, right ventricle
Path of Oxygen Transport
Lungs>Pulmonary Vein>Left Atrium>Left Ventricle>Aorta>Arterioles>Capillary>Body Cell
Path of Blood Transport
Heart>Artery>Capillary>Body Cells>Capillary>Vein>Heart
Path of Deoxygenated Blood Transport
Capillary>Venules>Vena Cava>Right Atrium>Left Ventricle>Pulmonary Artery>Lungs
Purpose of Red Blood Cell
To carry oxygen around the body
Substances needed for energy, cell functioning, growth & repair
5 Main Groups of Essential Nutrients
Carbohydrates, Proteins, Lipids (fats), Vitamins, Minerals
Provides an immediate source of energy, composed of carbon, hydrogen and oxygen
Two Types of Carbohydrates
Simple carbohydrates (single sugar units that are absorbed directly into the bloodstream, eg Glucose, Fructose) and complex carbohydrates (carbs that break down into simple carbs, eg Starch, Cellulose)
Provides raw materials for cell growth/repair of damaged/worn out tissue and can also supply minimal energy
Lipids (Fats)
Provides slow energy, also used to store energy in the body and insulate it
An organic compound and an essential nutrient that an organism requires in limited amounts
Are needed in small amounts to help the body function properly
Essential Non-Nutrients
Water and fibre
Enzyme that breaks proteins down into amino acids
Enzyme that breaks carbohydrates down into glucose
Enzyme that breaks lipids down into fatty acids
Digestive System
A group of organs working together to convert food into energy and basic nutrients to feed the entire body, used to supply the body with the nutrients it needs to function, supplies glucose to cells for aerobic cellular respiration
Mouth (Digestive System)
Where digestion starts; amylase in your saliva begins the process of chemical digestion, the teeth mechanically breaks down food and the tongue rolls the food around into a slimy, slippery ball called bolus (Digestive System)
Oesophagus (Digestive System)
The second stage of the digestive system; the bolus is then pushed through by peristalsis, then is transported to the stomach for temporary storage and further digestion (Digestive System)
A muscular contraction in the oesophagus that pushes food down
Stomach (Digestive System)
A muscular organ located on the upper left side of the abdomen; where food enters from the oesophagus, secretes hydrochloric acid and protease, muscles contract to churn food (Digestive System)
What the small intestine is lined with; finger shaped to maximise surface area increasing the efficiency of nutrients being absorbed into the surrounding capillaries
Liver (Digestive System)
The organ that produces bile (Digestive System)
Gallbladder (Digestive System)
Stores bile, a combination of fluids, fat, and cholesterol. Bile helps break down fat from food in your intestine. The gallbladder delivers bile into the small intestine (Digestive System)
A dark green to yellowish brown fluid, produced by the liver to aid the digestion of lipids in the small intestine; is transported to the gall bladder via the bile ducts to be stored
Pancreas (Digestive System)
Where lipase, amylases & protease are made, then secreted into the small intestine (Digestive System)
Large Intestine (Digestive System)
Undigested food moves from the small intestine to the colon of the large intestine to absorb water and other essential nutrients (Digestive System)
Rectum (Digestive System)
The final part of the digestive system; where the faeces is stored (Digestive System)
Anus (Digestive System)
Where the faeces is excreted out of the body (Digestive System)
Mechanical Digestion
Food is broken down into smaller fragments to move around the body easily
Chemical Digestion
Breaking down food into simpler nutrients by enzymes
The net movement from an area of high concentration to an area of low concentration
Any process that gets rid of unwanted products or waste
Excretory System
Rids the body of unneeded products and wastes; main organs are the skin, liver, lungs, kidneys
Skin (Excretory System)
Excretes salts and water as sweat (Excretory System)
Lungs (Excretory System)
Excretes carbon dioxide and a small amount of water vapour (Excretory System)
Liver (Excretory System)
Breaks down toxins for excretion (Excretory System)
Kidneys (Excretory System)
Excrete the unused waste and products of chemical resources (eg urea) and any other chemicals that may be used in excess (water) (Excretory System)
An organ found in the vertebrates, more than 100 functions; removes fats and oils from the blood/modifies them for storage, gets rid of excess proteins by converting them to urea for excretion in urine, changes dangerous/harmful/poisonous substances so they are harmless
2 spongy, bean-shaped organs found on the left and right sides of the body in vertebrates, each one contains <1 million units called nephrons; removes excess water and minerals ions, takes place in stages: 1. filtration 2. reabsorption 3. formation of urine (excretion)
Over 1 million found in the kidneys; cleans the blood by removing excess water and mineral ions
Nervous System
Assists the body in keeping in control and coordinating other body systems so that they can work together and function effectively; composed of the CNS/PNS
Central Nervous System (CNS)
The complex of nerve tissues that control the activities of the body, comprising of the brain and spinal cord
Peripheral Nervous System (PNS)
The nervous system outside the brain and spinal cord, connects the CNS to the rest of the body
A specialised cell that transmitts nerve impulses; a nerve cell
Structure of a Neuron (Contain)
Contains nucleus, cell organelles, cytosol, cell membrane, myelin sheath, cell body (soma), dendrites, axon
Structure of a Neuron (Explanation)
The cell body has sensitive branching extensions called dendrites, dendrites possess receptors that can receive messages from other cells, the messages move to the axon through an electrical impulse, an axon is covered in myelin, which speeds up conduction
3 Main Parts of a Neuron
The soma (cell body), dendrites, axon
Types of Neurons
Sensory neurons (part of the PNS), interneurons (part of the CNS), motor neurons (part of the PNS)
Sensory Neurons
Part of the PNS, found in sense organs, detects changes in the environment; messages about changes are relayed to an interneuron
Part of the CNS, carries impulses through the spinal cord and the brain; impulses are relayed from the interneurons to the motor neurons
Motor Neurons
Part of the PNS, forms part of a pathway along which impulses pass from the brain or spinal cord to a muscle or gland; receives impulses from the interneurons and cause a response in an effector organ
Endocrine System
Uses messengers called hormones, like the nervous system, it detects a change in a variable and responds accordingly
Control and regulate functions such as metabolism, growth and development
The gap between neurons; a nervous impulse reaches the axon terminal of a neuron where tiny vesicles containing neurotransmitters are transported to the membrane, these chemicals are then released into the synapse
Chemicals that are released into the synapse; moves across the synapse and bind to receptors on the membrine of dentrites of the next neuron
Reflex Arc
Actions that happen without thinking, only involves a few neurons, message doesn't go to the brain
Sense Organs
Used to detect stimuli, contain cells called receptors; 5 types, smell, sight, temp, motion, pain
Detects smell/taste
Detects sight
Detects heat/temperature
Detects motion/sound
Pain Receptors
Detects pain