science 9

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SNC1D Grade 9 Science Exam

Final Exam Study Notes Grade 9 Academic

Biology-Reproduction

Phases of Mitosis

Prophase

Chromosomes duplicate

Nuclear membrane splits

Metaphase

The double stranded chromosomes are lined up in the center

Held using spindle fibres

Anaphase

The chromosomes split equally apart towards each poles of the cell

Telophase

The chromosomes become totally apart

The cell’s nuclear membrane reforms

Cytokinesis

The process of splitting nuclear material equally in cell division

Meiosis

The process of creating sex cells that have half the amount of chromosomes that mitosis cells do

Cell Theory

All living things are made up of cells

All cells come from pre existing cells

Cells are the basic functional units of life

Cell inhibition lab

Cell inhibiting substances stops or dramatically slows down mitosis and cell division

The sprouts treated with cell inhibiting substances grew slower than the control

Applications: cancer treatment, weed removal, hair removal

Asexual vs sexual reproduction in changing environments

Advantages

Sexual – diversity

Asexual- no partner, fast reproduction

Disadvantages

Sexual- takes too much time to reproduce

Needs a partner

Asexual- Low diversity

Asexual reproductive strategies

Binary Fission

Single celled organism divide into 2 cells of the equal size

Budding

Single cell grows and breaks off to become a mature creature

Fragmentation

Part breaks off and becomes a mature creature

Spore Formation

Creates identical but smaller cells

Sexual reproductive strategies

Conjugation: Sexual reproduction involving 2 bacteria coming into contact with each other and forming an exchange of genetic information

Hermaphrodites: organisms with both male and female reproductive organs. Any 2 hermaphrodites can exchange genetic information

Plant reproduction

Pollination

Pollen floats by wind or carried by insects

Pollen lands on stigma

Stigma: Absorbs the pollen and sends it through the style and into the ovaries

Goes down the style

Style: Vertical tube where the pollen is transported down to the ovaries

Goes to ovary and fertilizes the egg

Ovary: Houses and fertilizes the egg

Anther and filament produces the pollen

Anther: Houses the pollen

Filament: Transports nutrients and pollen into the anthers

Male plants do not have ovaries

Plants

Human Reproductive Organs

Female reproductive organs

Reproductive Technology

GMF- process of changing the genetic sequence of plants in order for more advantage economically and plant wise for the farmer

Chemistry- Matter

Chemical VS Physical Properties

Chemical Properties

Reactions with acid

Combustibility

Physical Properties

Colour

Texture

Odour

Taste

Lustre

Clarity

Ductility – the ability to be pulled into wires

Malleability- the ability to be pushed or hammered into different shapes

Chemical VS Physical Changes

Chemical

Permanent change in colour

Gas or bubbles form

Precipitate forms in liquid

Light or heat is absorbed or released

Not reversible

Physical

Changes in state

Changes in shape

Dissolve

Reversible

WHMIS- Workplace Hazardous Material Information System

Classifying Matter

Pure Substance: One substance

Solution: a homogenous mixture that looks like one

Mixture: a heterogeneous mixture that looks as though as it is made of multiple parts

Compounds: a pure substance made of one or more elements

Pure Substance vs. Compound

Pure substance is made of one element and one substance, compound is made up of one or more elements.

Heterogeneous VS Homogenous

Heterogenous- Looks like it is made up of more than one part

Homogenous- Looks like one part

Subatomic Particles

Protons, Neutrons, Electrions

ION: an atom that has become charged by gaining or losing one or more electron to fill its outer orbital

Valence Electron

The number of electrons in the outer orbital

Organizing elements

Alkali Metals

Very reactive

Metallic

1 valence electron

Opaque

Alkali Earth Metals

2 Valence electrons

Found on earth

Metallic

Opaque

Solid

Halogens

Non reactive non metal

7 valence electron

Gas

Translucent or transparent

Noble Gases

Very stable

Gas

Translucent

8 valence electrons

Density

D=M/V

Isotopes

Elements with the same number of protons but different mass due to different number of neutrons

Physics- Electricity

Static Electricity

Electricity that does not move from where it was charged

Charging

Friction

Contact

Induction

Laws of electric charges

Like charges repel

Unlike charges attract

Insulators vs. Conductors

Insulator: a material that blocks electricity from passing

Does not allow electrons to flow from one atom to another

Conductor: any substance that allows electrons to move freely from one atom to another

Inducted Charge Separation- Explained in diagrams

Current Electricity

Current electricity flows while static electricity does not

Circuit diagrams

Battery

Loads

Resistor

Light bulb

Switch

Ammeter

Voltmeter

Series Circuit

Only one path for the electrons to flow

Parallel Circuit

More than one path for the electrons to flow

Voltmeters

Measures potential difference

Potential difference is the amount of energy a batter has to push the electrons across a circuit

Attached in PARRALELL

SI unit: V – Volt

Ammeter

Measures current

Current is how much electrons are flowing through a circuit

Attached in series

SI unit: A – Amperes

Ohm’s Law

V=IxR

Graph of voltage vs. current, resistance is voltage over current

States that the resistance is always proportional to the voltage and current

Ohmic Resistors

Any load that will not change the resistance regardless of change in current or voltage

Series VS Parallel circuits

Series

Vtotal=V1+v2+v3…

Itotal=I1=I2=I3…

Rtotal=R1+R2+R3…

Parallel

Vtotal=V1=V2=V3…

Itotal=I1+I2+I3…

Rtotal= 1/R1+1/R2+1/R3…

Electrical energy

Energy that is given off through electric charges

Energy: anything that allows us to move.

E=IxTxdeltaT

E=PxT

Electrical Power

The rate at which electrical energy is being used

P=E/T

P=VxT

Percentage Efficiency

%efficiency=(output energy/Input energy) x 100%

Astronomy

Big Bang Theory

At time zero, all matter was packed into an extremely dense small space

Created pressure, energy, and heat

Huge explosion, Big Bang, occurred causing material to erupt outwards from “the centre of the universe”. Today, the universe is still expanding.

Light Year

Measures the amount of distance traveled by light in 1 year. Used to measure distances in space

Planets

Inner planets

Mercury

Venus

Earth

Mars

Outer planets

Jupiter

Saturn

Neptune

Ringed planets

Jupiter

Saturn

Neptune

White Dwarf Star

The death of a small star

Small, hot, dense, white stars