What is the function of a cell's nucleus?
To act as a brain
To control the movement of substances into and out of the cell
To control the activities of the cell
What is the function of the ribosomes?
To absorb light energy for photosynthesis
To act as the site for protein synthesis
To release energy by respiration
Metal atoms form...
Ribosomes are the site of protein synthesis. Mitochondria are the site of energy release by respiration
Ribosomes are the site of protein synthesis. Mitochondria are the site of energy release by respiration.
Positive ions by losing electrons
Alveoli is another word for windpipe
In what period of its life is our Sun?
Main sequence
Major sequence
Minor sequence
A very massive star may explode at the end of its life. This is a....
Supernova
Neutron star
Black hole
Respiration is a chemical reaction that happens in your cells
Why does sodium chloride have a lower melting point than magnesium chloride?
Its positive ions are smaller and have a smaller charge
Its positive ions are larger but have a smaller charge
Its positive ions are smaller but have a larger charge
When the diaphragm contracts, it moves down and there is more room, so air rushes into the lungs.
Which salt is made when calcium carbonate reacts with hydrochloric acid?
Sodium chloride
Calcium chloride
Calcium sulfate
The Alveoli are shaped like it is to increase the surface area
Carbon Dioxide and Water are produced from Respiration
The symbol equation for neutralisation is:
acid + alkali → salt + water
H+(aq) + OH-(aq) → H2O(aq)
H+(aq) + OH-(aq) → H2O(l)
A suitcase travels on a conveyor belt. What happens to its momentum if the belt speeds up?
It increases
It stays the same
It decreases
What happens to the suitcase's momentum if the conveyor belt goes round a corner?
It changes
It is not possible to know
What happens to the total momentum of a firework when it explodes?
When acids and alkalis dissolve in water...
Acids produce hydroxide ions and alkalis produce hydrogen ions
Acids produce hydrogen ions and alkalis produce hydroxide ions
Acids and alkalis produce hydrogen ions
Energy is released in stars by...
Nuclear fusion
Nuclear fission
Gravitational attraction
Stars form from dust and gas due to...
In around four billion years, what will our Sun become?
A red dwarf
A red giant
A red super giant
Which of these is not a natural source of radiation?
Food and drink
Medical x-rays
Cosmic rays
What do radiation badges do?
They emit radiation for workers to use
They monitor the radiation dose a worker receives
They protect a worker from absorbing radiation
The half-life of an isotope is 1 hour. How long will it take for the count rate to fall to one-quarter of the starting rate?
1 hour
2 hours
4 hours
Atom X has 7 neutrons and 7 electrons. It decays to form atom Y with 5 neutrons and 5 protons...
The decay was alpha decay
The decay was beta decay
The decay was gamma decay
Atom X has 7 neutrons and 7 electrons. It decays to form atom Z with 6 neutrons and 8 protons
Organisms such as bacteria and Amoeba are described as ❌ while larger organisms are multicellular
The process of getting oxygen into your lung is
A chemical process in your cells is respiration breathing( respiration, breathing )
Getting carbon dioxide out of your lungs through breathing respiration( breathing, respiration )
takes place in mitochondria
is a process that releases energy
Respiration is the process that releases energy from food. Why is this done?
In mammals - to maintain a constant body temperature
To allow molecules to diffuse through membranes
To enable muscles to contract
To build larger molecules from smaller ones
In plants - to build up sugars, nitrates and other nutrients into amino acids
Label the Animal Cell diagram
Por favor espera - en proceso…