Body coordination Flashcards
What are enzymes?
Proteins that help speed up chemical reactions but don’t get used up
What is a catabolic reaction?
A large molecule is split into smaller ones
What is an anabolic reaction?
A reaction where smaller molecules join to form a larger molecule
What is a substrate?
The substance that is altered during a chemical reaction
How to enzymes work?
They are specific to a particular type of substrate and attaches to it (lock and key model)
What do carbohydrates break down into during digestion?
Glucose
What do proteins break down to during digestion?
Amino acids
What do lipids break down to during digestion?
Fatty acids and glycerol
What is diffusion?
The movement of particles in a substance from a high concentration to a low concentration
What is the purpose of the respiratory system?
It takes oxygen into the body and removes waste carbon dioxide
What is the purpose of the circulatory system?
Carries materials to and from cells via arteries, capillaries and veins
What initiates the heart’s rhythm?
The pacemaker (SA node)
How does the pacemaker initiate the heartbeat rhythm?
It stimulates both atria to contract, the stimulus reaches the tissue between the atria and ventricles, the AV node stimulates both ventricles to contract
What is ventricular fibrillation?`
A condition in which the impulses in the ventricles become disorganised and the muscles twitch spasmodically
What is a defibrillator?
A machine that delivers an electric current to the heart, in attempt to restore the heart’s natural rhythm
What are hormones?
Chemicals that act as messengers in the body and are secreted from endocrine glands.
Which hormone is released under stress or fear and what is its effect on the heart?
Noradrenaline, it increases the rate at which it beats, the strength of the contractions and how much blood it pumps (up to 5x)
In what ways do vigorous exercise increase the heart rate?
Increased cellular respiration which causes more CO2 in blood, receptors send messages to brain. Increased muscular activity pumps more blood back to the right atrium, it stretchers, stretch receptors send messages to brain.
What are receptors?
Specialised cells that detect stimuli changes
What is the negative feedback when you stop exercising?
Receptors in the aorta and carotid artery send messages to the brain to slow down heart rate
What are mitochondria?
Organelles in which cellular respiration take place and that produce energy
What are ribosomes?
Chemical reactions to produce proteins from amino acids that the body can use
What are lysosomes?
Organelles that treat wastes within cells by digesting dying cells, damaged organelles and diseases that have invaded the cell
What are the functions of the liver?
Breaks down hormones, breaks down haemoglobin, breaks down and modifies toxic substances and medicines, converts ammonia to urea
Which two organs are involved in the excretory system?
Liver and kidneys
What is metabolism?
All of the chemical processes that maintain life
What are the 2 groups of metabolism?
Reactions that break down organic matter, reactions that build complex molecules from simpler substances