Science 8 Review Questions For Final Exam
1. Define the following:
a. nucleus: The organelle that controls all the activities within a cell.
b. mitochondrion: The energy producers in a cell that carry out cellular respiration to produce energy for the cell.
c. ribosome: Cell parts that assemble proteins (organelles).
d. cell membrane : A thin protective covering that separates the interior of a cell from its surroundings controls the movements of particles into and out of the cell.
e. Condensation: The process of changing state from gas to liquid
f. Sublimation: The process of changing state from solid to gas without going through the liquid stage.
g. Solidification: Process of changing from liquid to solid by removing heat.
h. Evaporation: Process of changing state from a liquid to a gas.
i. Freezing: The temperature at which a liquid becomes a solid as heat is removed.
j. Density: The mass of a given volume.
k. Mass: The amount of matter in a substance or an object: The more matter, the greater the mass.
l. Weight: The amount of force on an object due to gravity.
m. anaphylactic shock: An allergic reaction that can result in swelling, breathing difficulty and sometimes death.
n. Osmosis: The diffusion of water particles through a selectively permeable membrane: particles move from high concentration to low concentration.
o. Fluid: A form of matter that can flow; liquid and gases are fluids
p. Solid: Having 3 dimensions (length, breadth and thickness), interior completely filled up.
q. Gas: A substance possessing molecular mobility and the property of indefinite expansion.
r. Amplitude: The height of a wave crest or depth of a wave trough as measured from the waves rest point.
s. Frequency: in a wave the number of repetitive motions or vibrations that occur in a give n time. Measured in cycles per second or hertz.
t. Hertz: cycles per second; measures the frequency of wave.
u. Wavelength: The distance from one point on a wave to the same point on the nearest wave.
v. Transparent: allowing light to pass through freely so that images are seen clearly
w. Translucent: allowing some light rays to pass through but not enough to see objects clearly.
x. Opaque: Absorbing or reflecting all light and not allowing any to light to pass through
y. concave lens: A lens that is thinner and flatter in the middle than around the edges: reflects light rays so they spread out
z. convex lens: A lens that is thicker in the middle than around the edges, focuses light rays as a focal point.
2. How do plant cells differ from animal cells?
Plant cells have cell walls and chloroplasts while animal cells do not. The vacuoles in plant cells are larger than those in animal cells.
3. What is photosynthesis?
The process in which carbon dioxide and water react in the presence of sunlight to produce glucose and oxygen.
Formula:
4. Draw a flow chart illustrating the following terms in the correct order: organs, cells, tissues, living things, organ systems.
Living things Þ organ systems Þ organs Þ tissues Þ cells
5. What role does oxygen play in the body?
Oxygen is one of the reactants in cellular respiration, a process which produces energy for our body.
6. Why do people with allergies take antihistamines?
People take antihistamines to reduce the symptoms cause by the release of histamine. (an allergic reaction).
7. What are the different components of blood and what are their roles?
Plasma: clear, yellowish fluid that contains numerous proteins, minerals and other substances
Red blood cells: Carry oxygen to the cells and carry carbon dioxide to the lung
White blood cells: fight infection and prevent the growth of cancer
Platelets: clots the blood when a cut happens.
8. Energy used by organisms to help them survive comes from the sun.
9. Five characteristics of a living thing are:
a. They are made out of cells
b. They react to stimuli
c. They take in and use energy
d. They are able to grow and reproduce
e. They get rid of waste
10. Why doesn’t the trachea collapse when a person inhales?
The trachea doesn’t collapse because C-shaped bands of cartilage maintain the tubular shape of the trachea.
11. What do the capillaries in the alveoli do?
They carry blood so that CO2 can diffuse out and oxygen can diffuse in
12. Which nutrient is used for quick energy?
Carbohydrates are used for quick energy.
13. What do proteins provide for the body?
They provide building blocks for the cell
14. Why is cigarette smoking bad for you?
Many of the chemicals in a cigarette are carcinogenic. Smoking causes the alveoli walls to lose their elasticity and it destroys the cilia lining so that dirt trapped in the mucus cannot be removed easily.
15. What does the left ventricle of the heart do?
The left ventricle pumps blood into your body (blood has already gone to the lungs and is oxygenated)
16. What does the right ventricle of the heart do?
The right ventricle pumps blood to your lungs. (Blood has just come from the body and needs to go to the lungs to get oxygenated.)
17. How do you calculate total magnification?
Total magnification= low power objective lens * eyepiece lens
18. What is the proper way to carry a microscope?
One hand on the handle, one hand bracing the bottom
19. List the following waves from shortest to longest:
a. x-rays
b. ultraviolet rays
c. infrared rays
d. gamma rays ANSWER: D, A, B, C, E
e. microwaves
20. How is HIV transmitted?
HIV is transmitted through bodily fluids: either through blood, or exchange of sexual fluids.
21. What is the relationship between wavelength and frequency?
It is an inverse relationship
22. What unit is used to measure frequency?
Cycles per second (cycles p/s) or Hertz (Hz)
23. What is kinetic energy?
Kinetic energy is the energy of motion. For example: Ball falling off a cliff will gain more kinetic energy as it falls, reaching maximum just before it hits the ground.
24. Why are solids denser than gases?
Solids are higher density than gases because the atoms and molecules that make them up are closer together. This is because the atoms/molecules in the solid are vibrating more slowly (less energy= are colder), they are vibrating more quickly when they are hot (more energy=hotter).
25. What units are used for measuring:
a. Force Newtons (N)
b. Pressure Pascals (Pa)
Kilopascals (kPa)= 1000 Pa
26. What is the most common device for measuring air pressure?
Barometer
27. What percentage of the Earth is freshwater?
3%
28. How do tides differ from currents?
Tides are the rise and fall of the ocean, while currents are the movement of ocean water in a particular, unchanging direction.
29. Name three factors that affect surface currents in the ocean.
a. Wind action
b. Earth’s spin
c. Shapes of the continents
30. List five different types of forces.
1. Tension force
2. Gravitational force
3. Frictional force
4. Elastic force
5. Electrostatic force
6. Magnetic force
31. Outline the Kinetic Molecular Theory
1. All matter is made up of very small particles
2. There are empty spaces between particles
3. Particles are constantly moving. The particles are colliding with each other and the walls of their container
32. Describe how winds and ocean currents influence regional climates.
Water warms up slower than land, and it moderates the land temperature.
Other Important Information to Know
Systems in the Human Body
Circulatorymoves blood, nutrients, gases, and wastes / Digestive
takes in and breaks down food, absorbs nutrients, gets rid of solid waste / Respiratory
controls breathing and exchanging gases in lungs and tissues
Excretory
removes liquid and gas wastes / Immune
- defends the body from infections / Endocrine
makes hormones
Reproductive
has organs for producing offspring / Integumentary
- (skin, hair, and nails)
- protects the body / Skeletal
has bones that support the body and work with muscles to move the body
Muscular
has muscles that work with bones to move the body / Nervous
has nerves that detect, signal, and respond to changes in the environment
Formulas
Density (D) = mass (m) or D = m
volume (v) v
Pressure (P) = force (F) or P = F
area (A) A
Plant and Animal Cell Parts
Food, Nutrients, Energy
The Heart
The Heart and Lungs
Crest, Amplitude, and Trough
Wavelengths
Light and the Law of Relection
Viscosity
The Eye
The Water Cycle
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Final Exam Review
BC Science 8
Eric Hamber Secondary – Learning Strategies Centre