Energy
What is the unit of energy?
Joule (J)
What is the unit of current?
Ampere (Amps)
What charge does a proton have?
Positive
Where is DNA stored in the cell?
Nucleus
What is the name of the blood vessel that carries blood away from the heart?
Artery
Name five types of energy store.
Kinetic, thermal, chemical, gravitational potential, elastic potential, electrostatic, magnetic, nuclear
Which wire in a plug is green and yellow?
Earth wire
What is the name of a bond formed between a metal and a non-metal?
Ionic bond
What type of cell has no nucleus?
Bacteria (Prokaryote)
What is the function of red blood cells?
To carry oxygen
What is the equation for kinetic energy?
Kinetic Energy = ½ × mass × speed²
State the potential difference of the UK mains electricity supply.
230V
Why do ionic compounds have high melting points?
Strong electrostatic forces between oppositely charged ions
Why do we stain cells with iodine before looking at them through a microscope?
To see them more clearly (staining)
What enzyme breaks down starch?
(It's in your saliva)
Amylase
What does insulation in a house reduce?
Energy transfer (heat loss)
What is the equation linking charge, current and time?
Charge = Current × Time (Q = I × t)
Why can graphite conduct electricity?
It has delocalised electrons that can move
What is the function of mitochondria?
Release energy during respiration
What is the role of the alveoli?
Gas exchange (oxygen in, carbon dioxide out)
A 2kg object is lifted 5m. How much gravitational potential energy is gained? (g = 10 N/kg)
GPE = mass × gravity × height = 2 × 10 × 5 = 100 J
A 3Ω resistor has a current of 2A. What is the potential difference across it?
V = I × R = 2 × 3 = 6 V
Explain why metals are malleable.
Layers of atoms can slide over each other
Explain how a root hair cell is adapted for its function.
Large surface area for absorbing water and minerals
Explain how the small intestine is adapted for absorption.
Large surface area (villi), thin walls, good blood supply