Science 14 Unit C: From Life to Lifestyle

Chapter 8

Structure and Function of Plant and Animal Cells

WORKBOOK

Name: _____________________________

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8.1 – A Closer Look pp. 158-164

Read pp. 158-159

Before the invention of microscope technology, scientific studies were rudimentary. Much of the work was based on trial and error.

The development of microscopes allowed scientists to see organisms that were previously invisible to the naked eye

o Early microscopes were pieces of curved glass (convex lens) that could bend light and focus it on one spot, much like a magnifying glass

o Originally able to view objects 30 times their actual size (Figure 8.1 – p. 158)

o saw “beasties” (bacteria) when magnified 200 times (Figure 8.3 – p. 158)

Modern compound microscopes have a stronger magnification than earlier devices

and use light to illuminate objects being viewed. (Figure 8.5 – p. 160)

o magnifies objects 400 to 1000 times their actual size

There are two types of electron microscopes that magnify more than 600 000 times by relying on a beam of electrons rather than light

o Object or specimen must be dead and covered in chemicals to observe using a transmission electron microscope (TEM)

o living organisms are examined with a scanning electron microscope (SEM) where electrons pass over the specimen to produce a 3D image

o see microscopic images on Figure 8.4 – p. 159

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Contrast and Staining o Scientists learned that staining cells improved the contrast between internal

cell parts. o Unstained cells are virtually colorless with little contrast between parts. o Manipulating the light source (diaphragm) allows you to alter the contrast of

different structures in a cell.

Properly Handling a Microscope o Be Careful!! o Carry it with 2 HANDS: one on the arm and the other on the base o Clean only with a soft cloth/tissue o Make sure it’s on a flat surface o Don’t bump it

Using a Microscope o Start on the lowest magnification and use the course adjustment knob to focus. o Never use the coarse adjustment knob on high magnification

you’ll break the slide!! o Increase the magnification and only use the fine adjustment to focus on medium

and high power.

What scientists learned from their observations, and the questions they continued to ask about cells, have led to many technological advances that depend on knowledge from microscopy.

The development of the microscope was a great boost for science. It allowed scientists who studied cells (referred to as cytologists) to observe details in plant and animal cells. These observations allowed them to develop greater understanding of the living world. Such advances include:

o blood work to identify disease mechanisms o urine analyses to detect various substances (Example: sugar) that are indicators

of disease (Example: diabetes) o the development of hybrid plants that have defenses against certain plant

diseases and parasites o genetic developments, such as cloning

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Discuss Figure 8.5 – p. 160

Use the following diagram to label the parts of a compound microscope.

hand lens curved glass for magnifying

dissecting scopes microscope consisting of two eye pieces, a low power lens, and a medium power lens

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Calculating Magnification Practice BLM 8-3

p. 163

Eyepiece magnification multiplied by magnification of the objective lens indicates the

total magnification of an object under a microscope.

Total Magnification = Ocular Lens x Objective Lens

Example:

Magnification of eyepiece: 5X

Magnification of objective lens: 4X

Total magnification: 5 x 4 = 20X

Complete the following chart for practice. Use the information to determine

the magnification of the specimens you are observing.

Eyepiece Objective Lens Show Your

Calculations Total

Magnification

(a) 5X 4X 5 x 4 = 20 20X

(b) 5X 10X

(c) 5X 40X

(d) 10X 4X

(e) 10X 10X

(f) 10X 40X

(g) 20X 4X

(h) 20X 10X

(i) 20X 40X

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Microscope Word Challenge BLM 8-8

1.

2.

3.

4.

5.

Clues

1. equipment used to examine specimens at 100X or more

2. often used to study the internal organs of lab specimens

3. improved by two Canadians named Prebus and Hillier

4. a magnifying device used in most schools

5. earliest form of the microscope

The letters in the boxes spell the name of a piece of magnifying equipment. What is it?

Piece of magnifying equipment: ___ ___ ___ ___ ___

Discuss CYU – p. 164 #1-3

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8.2 – Cell Theory pp. 164-165

Organization of Life

(cell hierarchy)

Atom – smallest unit of matter for both living and non living

Molecules – atoms grouped together form molecules

Organelle – part of a cell that carries out a specific function or role

Cell – smallest unit of life; the building block of all living organisms

from the Latin word cella, meaning small room

Tissue –cells combined to perform a specific task or function

Organ – two or more tissues combined work together to do a specialized role

System – any group of organs working together to perform a specialized role

Organism – any living thing that carries out all 7 activities necessary to survive

Cell Theory – accepted explanation supported by repeated experimental results

1. Cells are responsible for function and structure in all organisms. 2. All living things are made up of cells. 3. All cells reproduce from other living things.

i.e. cells are the smallest unit of life and come from other cells

Bacteria and amoebas are made of one cell

Humans are multi-cellular organisms

Discuss CYU – p. 165 #1-4

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Word Scramble BLM 8-12

Unscramble the letters to discover these key terms from your study of cell theory.

Use the definitions as clues to help you along.

Definition Scrambled Word Answer

a) when life processes are

present, an organism is

called this

V I G L I N

b) tissues combined to perform

a specialized role

G R O A N

c) activities necessary in

order to survive

F I L E S P E C S O R E S

d) part of a cell that carries

out a particular function

or role

L E G L A N O R E

e) cells combined to perform a

specific task or function

S U T I E S

f) the smallest unit of life

L C E L

g) life processes are not present

in this kind of object

G I N – V I N L O N

______________________

h) an explanation supported

by repeated experimental

results

H E R T O Y

i) made up of organs working

together

M E S S Y T

j) may consist of only one cell,

or many cells

S N A R G I O M

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8.3 – Plant & Animal Cell Structures pp. 166-173

A) Cell Membrane

separates inner cell from surrounding environment

semi-permeable (allows some materials in and keeps harmful materials out)

B) Cytoplasm

jellylike fluid

holds organelles in place

C) Nucleus

“brain” or control centre

directs overall cell activity

contains DNA

D) Vacuole

stores food, water, and waste materials

looks like an empty sac

E) Endoplasmic Reticulum (ER)

transports food, water, and waste materials

F) Mitochondrion

“powerhouse” releases energy in the cell

uses oxygen and digested food for energy

G) Golgi Apparatus

holds waste products until cell removes it

packages and transports proteins

specialized part of the ER

H) Cell Wall (only in plant cells)

protection and strength for cell.

non-living.

I.) Chloroplast (only in plant cells)

contains chlorophyll (green color)

helps collect sunlight for photosynthesis.

Discuss CYU – p. 173 #1-4

Animal

Plant

⇒Organelles

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Parts of the Cell BLM 8-13

Complete the chart by placing the missing information in the correct box. Identify

whether you were using the plant or animal cell, and which letter identifies the part. Use

the list of cell parts to label the diagrams below.

Cell Part Diagram Letter Function

cytoplasm

outer covering of a plant cell

outer covering of an animal cell

chloroplast

mitochondrion

transportation system inside the cell

Golgi Apparatus

control centre of the cell

vacuole

Animal Plant

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Organelle Crossword BLM 8-17

Across 1. semi-permeable; separates contents of cell from surrounding environment

4. collects sunlight; found only in plants

5. stores food, water, and waste

7. the “powerhouse”; releases energy in cell

Down 1. jelly-like substance

2. transports materials; known by initials

3. non-living; provides protection and strength

6. the control centre

Read pp. 174-175

Discuss CYU – p. 175 #1-4

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Word Search BLM 8-18

Complete the word search puzzle by finding the 23 key terms listed below.

Circle the words as you find them.

Hint: The words may be hidden in any direction, but they will always be in a straight line.

microscope

organelle

theory

vacuole

compound microscope

living

organism

ER

electron microscope

non-living

life processes

cell membrane

hand lens

tissue

nucleus

cell wall

dissecting scope

organ

cytoplasm

chloroplast

cell

system

mitochondrion

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Chapter 8 Review Questions

1. Who played a leading role in the development of the microscope? (8.1)

2. Sketch a microscope. Label its parts. (8.1)

3. State the cell theory. (8.2)

4. List the life processes of all living things. (8.2)

5. Use a chart to show the difference between living and non-living things. (8.2)

6. Identify the parts of an animal cell. (8.3)

7. Identify the parts of a plant cell that are not part of an animal cell. (8.3)

8. What two parts of the cell handle transportation of materials? (8.3)

9. How are the functions of a cell similar to the functions of a city? (8.4)

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Complete Chapter 8 Review Questions – p. 176 #1-8

Please record your answers below or on an attached sheet of loose leaf.