Y9 Exam: Sciences

Question 1

Function of NUCLEUS

Answer 1

Contains genetic material

Controls what happens in cell

Question 2

Function of CYTOPLASM

Answer 2

Where most chemical reactions take place, controlled by enzymes

Question 3

Function of cell MEMBRANE

Answer 3

Semi-permeable, controls movement of substances going in and out of the cell

Question 4

Function of MITOCHONDRIA

Answer 4

Where most energy is released by respiration

Question 5

Function of RIBOSOMES

Answer 5

Where protein synthesis happens

Question 6

Function of cell WALL

Answer 6

Strengthens cell

Question 7

Function of CHOLOROPLASTS

Answer 7

Contains chlorophyll which absorbs light energy for photosynthesis

Question 8

Function of VACUOLE

Answer 8

Filled with cell sap to help keep the cell swollen with water

Question 9

Specialised SPERM cell

Answer 9

Tail to propel them forwards
Streamlined shape to reduce resistance
Contains large numbers of mitochondria to give the cell it’s energy
Releases enzymes on contact with egg cell to digest a path through the outer coat of the egg

Question 10

Specialised ROOT HAIR cell

Answer 10

Long thin root hair which provides large surface area for absorption to happen

Question 11

Specialised RED BLOOD cell

Answer 11

No nucleus to increase volume of haemoglobin on cell

Very flexible so it can move through narrow blood vessels

Question 12

Magnification equation

Answer 12

Magnification = size of IMAGE | size of OBJECT

Question 13

Light microscope magnification equation

Answer 13

Total magnification = eyepiece lens X objective lens

Question 14

What are STEM cells?

Answer 14

UNSPECIALISED cells which can DIFFERENTIATE into any kind of human cell.

Question 15

Where can human stem cells be found?

Answer 15

Human EMBRYOS or adult BONE MARROW

Question 16

Uses of STEM cells

Answer 16

Stem cells have the potential to be used in new treatments for conditions such as Parkinson’s disease and paralysis.

Question 17

What is OSMOSIS?

Answer 17

The movement of WATER from a DILUTE solution to a CONCENTRATED solution across a SEMI-PERMEABLE membrane

Question 18

What is DIFFUSION?

Answer 18

The movement of PARTICLES from an area of HIGHER concentration to an area of LOWER concentration

Question 19

Why is diffusion important?

Answer 19

It allows cells to get oxygen and nutrients for survival

Question 20

The rate of diffusion is increases when:

Answer 20

Distance is decreased
Surface area is increased
Concentration gradient is increased

Question 21

What is the structure of an ATOM?

Answer 21

Atoms consist of electrons surrounding a nucleus that contains protons and neutrons

Question 22

How do you work out MASS number?

Answer 22

= protons + neutrons

Question 23

How do you work out how many NEUTRONS?

Answer 23

Mass number - Atomic number

Question 24

What is the ATOMIC number?

Answer 24

= Protons
= Electrons
Same number

Question 25

What is the Group Number?

Answer 25

= number of electrons in the outer shell

Question 26

What's the row/period?

Answer 26

= number of shells

Question 27

What is an ELEMENT?

Answer 27

An atom of ALL the SAME type

Question 28

What is a COMPOUND?

Answer 28

A mixture of different types of elements

Question 29

What is a MOLECULE?

Answer 29

At least 2 different atoms joined together

Question 30

Solid to liquid

Answer 30

Melting point

Question 31

Liquid to gas

Answer 31

Boiling point

Question 32

Structure of a SOLID

Answer 32

``` Close together Arranged in a regular pattern Held together by strong chemical bonds Can vibrate in a fixed position Can't move from place to place ```

Question 33

Structure of LIQUID

Answer 33

Close together Arranged in a random way The particles can move around each other

Question 34

Structure of GAS

Answer 34

Far apart Arranged in a random way The particles can move quickly in all directions

Question 35

Conservation of mass

Answer 35

Mass of reactants = mass of products | Matter cannot be created or destroyed

Question 36

Filtration

Answer 36

Method for separating an insoluble solid from a liquid

Question 37

Evaporation

Answer 37

Used to separate a soluble solid from a liquid

Question 38

Simple distillation

Answer 38

Method for separating the solvent from a solution

Question 39

Fractional distillation

Answer 39

Method for separating a liquid from a mixture of two or more liquids

Question 40

Paper chromatography

Answer 40

Method for separating dissolved substances from one another

Question 41

Properties of metal

Answer 41

``` High melting point Conducts electricity & heat Solid/rigid Dense Malleable Sonorous Ductile Shiny ```

Question 42

Group 1 metals (reaction)

Answer 42

Each group 1 metal reacts with water and forms a metal hydroxide and hydrogen gas. The reactivity is a measure of how easily a metal loses its outer electrons.