7-1 Worksheet 263f3x

Name

Class

Date

7.1 Life Is Cellular Extra Credit: answer the following on a separate sheet and attach. 1. State the cell theory. 2 Describe how the different types of microscopes work. 3. Distinguish between prokaryotes and eukaryotes.

The Discovery of the Cell 1. The invention of the

made the discovery of cells possible.

2. Robert Hooke used the name

to refer to the tiny empty chambers he

saw when he observed magnified cork. 3. German botanist Matthias Schleiden concluded that

are made of cells.

4. German biologist Theodor Schwann concluded that

are made of cells.

5. Rudolph Virchow concluded that new cells are produced from 6. The

.

combines the conclusions made by Schleiden, Schwann, and

Virchow.

Exploring the Cell True or false? 7. The size of the image formed by a light microscope is unlimited because light that es through matter is diffracted. 8. Fluorescent dyes help scientists see the movement of compounds and structures in living cells. 9. Transmission electron microscopes form a 3-D image of the surface of a specimen. 11. To study cells with a light microscope, different types of stains are usually available. Why is it generally more useful to stain eukaryotic cells than prokaryotic cells?

10.

In the second row of the table, draw diagrams to show how a sample of three yeast cells would look in the types of micrographs indicated in the top row of the table. Then, in the third row, describe how each image would be formed. A Comparison of Detail in Basic Types of Micrographs

Light Micrograph ( LM 500x)

A light microscope image is formed by

Transmission Electron Micrograph

Scanning Electron Micrograph

(TEM 4375x)

(SEM 3750x)

A transmission electron micro-scope image is formed by

A scanning electron microscope image is formed by a

. .

.

Add text to the circles to show the most important parts of the concept. Connect the circles with lines.

Exploring the Cell _____2. A scientist wants to examine the structures inside of a tiny bacterial cell. What is the best microscope to use for this job? a. scanning electron microscope

b. transmission electron microscope

_____3. Your science class is going to examine the one-celled organisms in pond water. What is the best microscope to use? a. light microscope

b. scanning electron microscope

_____4. Which of these microscopes would let you see the hairlike projections on the surface of a cells better? a. transmission electron microscope b. scanning electron microscope

A microscope allows scientists to study very small objects. It magnifies objects by focusing light or electrons. The chart below contains information about three kinds of microscopes. The middle column contains a description of each type of microscope. The third column describes ways each type of microscope is used. 1. Use the below to complete the chart.

Type of Microscope

Microscopes Description of Microscope Uses beams of electrons to examine thin slices of material Uses lenses to focus light on a specimen Uses beams of electrons to view the surface of a specimen

Uses of Microscope Provides twodimensional images of cell structures Enlarges cells or cell parts up to 1000 times Provides threedimensional images of cells

Prokaryotes and Eukaryotes Prokaryotes are simple cells. They lack a nucleus. Your body is made up of eukaryotic cells. Eukaryotes have a nucleus that holds DNA. They also have organelles. 1. Label the prokaryotic cell.

2. Label the eukaryotic cell.

13. Which category of cells—prokaryotic or eukaryotic—is your body composed of?

3. Compare and contrast the two types of cells by completing the table. Prokaryotic Cell Cell membrane Nucleus Cell size

Eukaryotic Cell

yes larger

Complexity

simpler

4. Your body is made up of prokaryotic

cells. eukaryotic

5. Bacteria are prokaryotic

cells. eukaryotic

6. Give two other examples of living things that are eukaryotic.

Prokaryotes and Eukaryotes 12. Complete the table about the two categories of cells. Two Categories of Cells Category Prokaryotic cells Eukaryotic cells

Definition

Size range

Examples