Science 9 Final Exam Review KEY - School District 41 Burnaby

Science 9 Final Exam Review KEYSafety and Chemistry1. Explain the particle model of matter and how temperature affects matter.-matter is made up of small particles-space between particles changes depending on temperature-particles are always moving-particles are attracted to one another/strength depends on types of particlesTEMPERATURE provides KINETIC ENERGY to particles meaning the move faster and further away fromone another2. Draw and explain each of the WHMIS symbols.Dangerous Container (outside)Dangerous Product (inside)3. List and explain the quantitative properties of matter.Quantitative: means physical properties than can be measured with NUMBERS4. Explain what is meant by the term pure substance.Pure Substance: made up only ONE kind of matter. There are 2 KINDS:1. ELEMENT 2: COMPOUND (2 or more elements)5. List the three subatomic particles; be sure to explain where they are located and their charge.

6. Explain the difference between families and periods.Noble GasesAlkaline EarthMetalsPeriods: HORIZONTAL ROWSFamilies: VERTICAL COLUMNS(transition and rare-earthmetal families are made up ofmultiple columns )7. List and locate the four families on the periodic table.*see above diagramAlkali Metals: highly reactive with oxygen and water, lose 1 electronAlkaline Earth Metals: not as reactive as alkali metals but will burn brightly, lose 2 electronsHalogens: highly reactive, poisonous, need ONE extra electron for full valence shellNoble Gases: usually do not react, have a FULL valence shell8. Describe the properties of metals, non-metals and metalloids.9. Explain how the periodic table is organized.10. Explain the difference between an atom and an ion.Atoms: HAVE NOT reacted, have NO chargeIons: : HAVE reacted, HAVE either a /- charge,

11. What is the electron arrangement for an atom?Atoms want to have full valence shells (ifpossible) and react by either GAINING orLOSING electrons to fix their outer/VALENCEshell12. Using a Bohr diagram, draw an atom and ion of the element aluminum.ATOM: no chargeunfilled valanceION: 3 charge/lost three electronsfilled valence13. Explain what is meant by the term valence electrons.Valence: outer shell electrons that are either LOST or GAINED when an atom REACTS to become an ION14. Explain the difference between ionic and covalent bonds.

15. Write the correct formula for the following compounds:a. Silver Nitrideb. Aluminum Phosphidec. Chromium II chlorided. Copper I Nitridee. Lithium dichromatef.Manganese IV sulphateg. Aluminum hydroxide16. Write the name for the following compounds:a. Na2Ob. Ag3Nc. CrBr3d. Fe2O3e. Mg3(PO4)2f.(NH4)3Pg. NaCH3COO

17. What two things can you determine from a chemical formula?-The MINIMUM number of each elements needed to make the compound-Whether the compound is ionic or covalent.18. Explain the difference between a physical and chemical change.PHYSICAL: change in state or dissociation of a compound into ions. NO new products madeCHEMICAL: a reaction where NEW products are made. It is not usually reversibleReproduction1. Explain the relationship between DNA, genes and chromosomes.-DNA is very long double-chained strands of genetic material.-Genes are SHORT sections along the DNA chain that code for either RNA messages or PROTEINS-Chromosomes are one double stranded DNA chain tightly wound up and held by HISTONE proteins mainlyforming X-shaped structures2. What is a mutagen and provide an example.Mutagen is something that causes a change to the GENETIC CODE in DNA. Examples are: cigarette smoke,X-rays, UV-light, pesticides, pollutants, some household cleaners, food additives3. What is meant by the term genetic code?Genetic code refers to the SEQUENCE of base pairs (A,T,C,G) found in a chromosome or DNA strand4. Draw and label an animal cell and give a brief explanation for each of the organelles.Cell membraneLayer that surrounds cells, controls what enters andleavesCytoplasmJelly like substance, houses organellesRibosomeInvolved in protein productionGolgi BodySorts and packages proteins for transportNucleusContains nuclear information about cell andimportant proteinsMitochondriaPowerhouse that is responsible for energyproduction of a cell

5. Explain the difference between neutral, positive and negative mutations.Neutral: Mutation in code that doesn’t alter the function of any proteins madePositive: Mutations that creates a change that POSITIVE for the organism and offers it an advantage in itsCURRENT ENVIRONMENT. *remember: if you change the environment the effect may not be positiveanymoreNegative: Mutation that affects the functioning of a protein leading to harm or a negative effect on anorganism. *remember: a negative mutation may not always stay negative if the environment changes6. Explain what is meant by complementary base pairing in reference to DNA?It means there are base pairs that always connect: A with T, and C with G7. List and describe the different types of proteins produced in the human body.Structural: make up the structure of the cellEnzymes: are necessary for biochemical reactions to happen in a cell (amylase in saliva is an example)Hormones: are chemical messengers that control functions (insulin is an example)8. Briefly explain gene therapy.Gene therapy usually involve using a harmless virus that is engineered to contain a gene that is not workingin a human. The geneticist will then try to target certain types of cell with the virus where the virus DNAcontaining the added gene will be inserted into the cells not working properly. The cells now will have theworking gene and make the protein.9. List and briefly describe the different types of asexual reproduction.Binary Fission: In bacteria where chromosome is replicated and each daughter is identical (very quick)Budding: Found in sponges and hydras, section of an organism can undergo mitosis and grow into a neworganism ad either stay attach or break offFragmentation: Found in some plants and animals (sea stars), where pieces of an organism can grow intonew organisms through mitosis

10. Describe the cell cycle.DNA is replicated11. Draw and describe what occurs at each stage of mitosis.12. What is the purpose of therapeutic cloning?The purpose of this therapy is to design ways to start using cloned cells to act as STEM CELLS that canbecome many different cell types. This creates a flexible starting cell that could be used to grow specializedtissues and organs for transplant. The idea here is that if you could find a way to grow organs from yourOWN cells, you could then transplant them in case of a disease or injury without your body rejecting thetransplant. Remember, right now transplant patients receive organs form OTHER people, and their immunesystem sees the transplants as foreign and attacks the new organ.

13. List and describe the parts of a flower.14. What is the advantage of sexual reproduction?It provides a way of shuffling genes during meiosis (when gametes/egg and sperm are made). This meansthat each resulting egg or sperm is different. This increases VARIABILITY in a population of organisms.Variation is important because it improves survival because some organisms will have an advantage overothers in an environment.15. What types of cells go through meiosis?Reproductive cells undergo meiosis to produce egg or sperm cells that have HALF the total number ofchromosomes as regular cells.16. What is the end product of meiosis?For sperm: there will be 4 different sperm cells with only half the regular number of chromosomesFor eggs: there will be 1 egg, and 3 polar bodies (die)

17. Explain the difference between haploid and diploid.18. What is meant by homologous chromosomes?

19. List and briefly describe the types of assisted reproductive technologies.Artificial Insemination: Sperm is collected and stored and later injected into a femaleIn Vitro Fertilization: Sperm and an Egg cell are collected and the process of fertilization occurs in a lab. Theresulting embryo is then implanted into the female.Gamete Intrafallopian Transfer: An egg and sperm cells are collected to create a mixture that is quicklyinjected into the woman’s fallopian tubes for fertilization to occur in the body.Intracytoplasmic Sperm Injection: Sperm cells and an egg are collected. In the lab, a single sperm cell isinjected into an egg cell resulting in a zygote that is then implanted into the uterus of the woman.Electricity1. What are the three laws of static charge?1. Like charges will repel, but unlike charges will attract.2. Electric charge is always conserved. It is something that is unable to be created or destroyed.3. Electric charge is always quantized (means it can be measured). It has a discrete value, which does notchange.

2. Explain the difference between an insulator and a conductor.Conductors: Allow forcurrent to flow easilyInsulators: Do not allow forcurrent to flow very easily3. Explain how current flows in a circuit.Current flows from the ANODE (-) to the CATHODE ( ) but conventional current isfrom CATHODE to ANODE

4. What is the definition of current and what device measures current?Current: The amount of CHARGE passing in a conductor past a point very second.1 AMP 1 Coulomb 6.24 x 1018 electrons1 Second1 second5. What is the definition of potential difference?The difference in charge from one area to another. The potential means that as electrons flow they havethe POTENTIAL to do work. Remember ONE VOLT 1 Joule/C of charge. The larger the difference in chargeor VOLTAGE the more energy that is available to be used for every charge moving in a circuit.In a circuit, the electrical energy is converted into light energy if a light is added to the circuit.6. List the parts of a circuit and give a description of their purpose.Acts as a conductor for electron flowStops the flow of currentAllows current to flowResists current and allows less current in a pathCreates voltage or the driving forceMultiple cells form a battery that creates more electric voltage or driving force for currentLight source that is a resistor. Electrical energy is converted into LIGHT and HEAT energy

7. Describe Ohm’s Law.Means that as VOLTAGE INCREASES so does the CURRENT8. Explain the difference between a dry and wet cell battery.Dry cells have a paste that creates a chemical reaction leading to the loss of electrons in the middle tube ofthe battery (CATHODE) and a gain of electrons in the outer area (CATHODE). This creates 2 ends of abatteryA wet cell has a liquid region where one side is positive and the other side negative with and - terminalsattached to each region.

9. Explain what happens to voltage and current in a series and parallel circuit.Means that as VOLTAGE INCREASES so does thSeries Battery: Voltage ADDStogetherParallel Battery: Voltage stays theSAME*Notice that in the parallelbattery that the battery life is 4times longer 10ah vs 40ahSERIESVoltage drops at aRESISTOR ADD equalto TOTAL VOLTAGECurrent is the samealong the entire pathPARALLELVoltage drops at eachresistor are EQUAL tothe TOTAL VOLTAGECurrent for each pathADDS to equal theTOTAL current*current is less for PATHSwith BIGGER RESISTANCE

10. What happens to resistance in series or parallel circuits?SERIESPARALLELResistance decreases. In above example, itmakes sense because HALF the current (ofTOTAL) enters each pathResistance ADDS together to sum theTOTAL because there is ONE path11. Draw a series circuit and parallel circuit; explain the difference.SERIESPARALLELSeries circuits have ONE path for current to flow. Parallel circuits have multiple paths for current to flow.12. Write down the units for the following: resistance, current, voltage, power, energy, timeResistance: Ohms (Ω)Current: Amperes (A)Voltage: Volts (V)Power: Watts (W)Energy: Kilowatt Hour (kW h)