Download Grade 8 Science Unit 4 Study Guide

Grade 8 Science Unit 4 Study Guide
The final unit test will be on pages 384 - 439.
Students need to know the following information:
1. Cell- the basic unit of life
Organelles- parts of the cell with a specific function.
2. The basic life processes common to all forms of life are:
1. All organisms grow.
2. All organisms move.
3. All organisms reproduce
4. All organisms
respond to stimuli in their environment.
3. Know the parts and functions of the parts of the compound microscope. (Pages
392, 393)
Picture in Unit 4 Review Supplementary material Smartboard file
Parts of a microscope
1. Body Tube: carries the image from the objective lens to the eyepiece
2. Revolving nosepiece: allows the objective lenses to be rotated and switched
3. Low power magnification: increases image size 4 times
4. Medium power magnification: increases image size 10 times
5. High power magnification: increases image size 40 times.
6. Stage Clips: keep the slide in place
7. Iris Diaphragm: controls the amount of light
8. Light source: provide light to improve the viewing of the specimen
9. Eyepiece lens: enlarges the image from the tube.
10. Arm: held to carry the microscope
11. Stage: the part that holds the slide
12. Course Adjustment knob: bring the image into coarse focus
13. Fine Adjustment knob: bring the image into fine focus
14. Base: supports the upper part of the microscope
Know how to calculate the magnification of an object viewed under the microscope.
(Page 393)—Extra Question
The eyepiece has a power of 10x. Each objective lens on the revolving nosepiece has its
own magnification.
When an object is placed under a microscope to be observed, the eyepiece power and the
objective lens power need to be multiplied. This will determine the magnification of the
object. For Example,
A specimen would have a magnification of 100x if observed under a medium objective
lens because--10x X 10x =100x
4. Know the function of all the organelles in plant and animal cells. (Page 405)
Picture in Unit 4 Review Supplementary material Smartboard file
Cell structure
Function
Nucleus
Control centre of the cell
Cytoplasm
Cell fluid
Cell wall
Provide rigid support to plant cells
Chloroplast
Site for photosynthesis in plant cells
Vacuole
Collects water and waste
Mitochondria
Convert food into energy for the cell
Plasma membrane
The outer boundary which contains the cell
5. Be able to state the cell theory. (Page 406)
Cell Theory
1. All organisms or living things are made up of one or more cells.
2. The cell is the basic unit of life.
3. All cells come from other living things.
6. Plant Cell
Animal Cells
Has a cell wall
Does not have a cell wall
Has chloroplasts (green)
Has no choloroplasts
Has fewer and larger vacuoles
Has more and smaller vacuoles
Cells are rectangular
Cells are round
7. Describe how to make a wetmount?
Preparation of a Wet Mount
Step 1: Use the dropper to place one drop of water (or iodine solution) on a clean glass
slide.
Step 2: Lay the specimen carefully on top of the drop.
Step 3: Take a clean plastic coverslip. Hold it between your thumb and forefinger and
touch the edge of the drop.
Step 4: Lower the coverslip onto the slide, so that the specimen is covered. (If you
have done this correctly, there will be no air bubbles under the coverslip.)
8. Know what mitosis is. (Pages 410, 411)
Mitosis- is the process of the division of cells. Examples include: skin cells divide to
produce more skin cells OR bacteria cell divides to become two cells.
9. Understand the levels of organization in living systems with regard to cells,
tissues, organs, organ systems, and organisms. (Page 422, 423)
Cells in our body will differentiate to become cells that have specific jobs.
There are cells that help us breathe, nerve cells that enable us to feel, skin
cells, brain cells, etc.
These cells aren’t very effective by themselves so they group together with
other cells just like them. When a bunch of similar cells group together , it is
called tissue such as nerve tissue, skin tissue,cardiac tissue,etc.
Bunches of tissue make up a specific organ such as skin, muscle and nerve
tissue can make up part of the stomach organ;
a group of organs make up a system such as the heart, and lungs make up the
respiratory system; and a group of systems such as digestive system,
circulatory system, etc. make up an organism.
CELL
TISSUE
→
SYSTEM
ORGAN
→
→
ORGANISM
→
10. Know the parts of the circulatory, respiratory, digestive, excretory, nervous, and
muscular systems. (Pages 428, 429) refer to information booklet (sbfile Human
Body Systems 2015)
11. Identify the main function of the following organ systems in keeping organisms
alive: circulatory, respiratory, digestive, excretory, nervous, and muscular. (Pages
428, 429) refer to information booklet (sbfile Human Body Systems 2015)
12. Describe the basic factors that affect the functions circulatory system, digestive
system, excretory system, nervous, and muscular system.
Diet, stress and exercise. (students should be able to elaborate in their own
words a little more on this topic)
13. How do the circulatory system, digestive system, excretory system and the
respiratory system all work together to provide you with energy? (Worksheet and
page 437) refer to Unit 4 Review Supplementary material Smartboard file
a) circulatory/respiratory
b) digestive/circulatory
c) nervous/muscular
14. What roles would diet, nutrition, exercise and stress have on the human body?
Same as 12.
15. How do our lifestyle changes affect our health?
refer to Unit 4 Review Supplementary material Smartboard file
16. What is the difference between heart rate and breathing rate? Describe how you would
take a person’s heart rate and breathing rate?
Heart rate: is how fast the heart pushes blood through the arteries.
Breathing rate: is how fast we inhale and exhale air.
You would take a person’s resting heart rate by taking a person’s pulse. This is a measure of how
many times their heart beats in a minute.
You would take a person’s breathing heart rate by counting the number of times a person
breathes in one minute. (one inhale and one exhale)
17. What is cellular respiration?
Cells need energy to function
properly. (Humans get their
energy from food, so DO cells.
The cells food is glucose (type
of sugar). Lots of food we eat
has glucose. (many fruits and
veggies)
How do the cells get the energy that is stored in
the glucose?
--The cells carry out a process called
cellular respiration.
-- Cellular respiration releases the energy
stored in the glucose by combining it
with oxygen. This chemical reaction
produces wastes in the form of carbon
dioxide and water.
Where does this chemical reaction
take place in the cell?
Mitochondria
energy for the
Glucose
+
Oxygen
cellular
functions
+
CO2
+
WATER
Food is ingested in the digestive system by first entering the mouth (saliva),
going down through the esophagus, small intestine and large intestine. The
glucose is picked up (circulatory system) by the mitochondria in the cells .
At the same time, oxygen enters our lungs (respiratory system), is picked up
(circulatory system) by the mitochondria in the cells .
Once the cells use this energy, they pass of their waste carbon dioxide and
water via the lungs (respiratory sytem) and the urethra (excretory system).