Respiration
What is respiration?
Respiration is a series of chemical reactions that happens inside every living cell.
Why are proteins imprtant for our bodies?
Protein is important for making new cells in the body andfor making haemoglobin.
What is solution?
A solution is made when a solute is dissolved in a solvent.
What are three sub-atomic particles in the atom and what are their charges?
Protons have a positive electrical charge (+)
Neutrons have no electrical charge
Electrons have a negative electrical charge (-)
What is weight?
It is strength of force of gravity which pulls object towards the centre of the Earth.
You can see the lungs are mostly holes. What is the name of these holes?
air sacs/alveoli
What is the function of fibre?
Fibre helps to keep food moving easily through the digestive system.
What is saturated solution?
If you keep adding a soluble solid to a beaker of water, there comes a point where no more of the solid will dissolve.
What is the nucleus of an atome made up of?
The nucleus of an atom is made up of protons and neutrons.
When forces are equal in size and opposite in direction?
The forces are balanced
There are also a lots of very tiny blood vessels in the lungs, wrapped around the air sacs. What is the name of these blood vessels?
Capillaries
Name three types of joints in our body.
Fixed joint
Hinge joint
Ball-and-socket joint
Explain difference between a chemical element, chemical compound and a mixture.
A chemical element is a species of atoms that have a given number of protons in their nuclei, including the pure substance consisting only of that species.
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds.
A mixture is a material made up of two or more different chemical substances which are not chemically bonded.
What is a pure element?
If an element is pure it means that every one of its atoms is exactly the same and made just from one type of atoms.
Unbalanced forces cause change in movement, what change?
speeding up, slowing down or changing the direction
What happens with diaphragm muscle during inhaling?
It contracts and moves downwards.
Muscles are attached to the bones by tough cords called what?
Tendons
How does temperature affect solubility?
The higher temperature the faster substance dissolved.
If a gold has 17 carats what is its purity? In percentages?
71%
What is the standard unit for speed?
metres per second
During inhaling volume in lungs increases. What happens with pressure inside the chest cavity?
It decreases.
What are the antagonistic muscles?
Antagonistic muscles are pair of muscles where one is contracting and the other one is relaxing and then it happens the other way around.
What is independent variable, dependent variable and control variable?
The variable you change is called the independent variable.
The variable you measure is called the dependent variable.
The variable you keep the same is called the control variable.
If silver has mark of 913 what purity is it? State in percentage.
91,3%
What is the equation for speed?
speed = distance / time