Introduction to Cells and Microscopes

Question 1

What are cells?

Answer 1

Cells form the parts of any living organism and carry out all of its functions.
Cells are the basic units of structure and function in all living things/organisms.
Cells obtain oxygen, food, and water.
Cells also get rid of wastes, such as carbon dioxide.
The food you eat provides your cells with energy. They work together and help you to stay alive.

Question 2

What does an organism refer to?

Answer 2

Something that is living

Question 3

When were living organisms classified?

Answer 3

Until the 1500s

Question 4

What did the invention of the microscope open up?

Answer 4

A whole new world-the microworld

Question 5

Robert Hooke (1665)

Answer 5

Viewed dead cork (from a tree) under the microscope and called what he saw “cells” because they looked like little rooms.

Question 6

Anton Von Lewerhook (mid-1600s)

Answer 6

Designed the first microscope and viewed pond water; he called the microorganisms “beasties” or “animalcules” (today bacteria and protists).

Question 7

Matthias Schleiden (1830s)

Answer 7

Concluded after looking at plants that “all plants are made of cells.”

Question 8

Theodor Shwann

Answer 8

Concluded after looking at all animal tissues that “all animals are made of cells.”

Question 9

Rudolf Virchow

Answer 9

concluded that all cells come from other cells

Question 10

The Cell Theory

Answer 10

All the scientists contributed to the cell theory.
The Cell Theory has three main parts:
All organisms are made up of one or more cells.
The cell is the basic unit of structure and function in all living organisms.
All cells come from cells.

Question 11

Simple Microscope

Answer 11

Has one lens
Example: magnifying lens, glasses

Question 12

Compound-Light Microscope

Answer 12

Has more than one lens – lenses are located in the eyepiece and revolving nosepiece/objective lenses
Uses light as a source
Produces a two-dimensional image

Question 13

Magnification

Answer 13

The change in apparent size of the object

Question 14

Total Magnification

Answer 14

The powers of the eyepiece times the powers of the objective lenses

Question 15

Scanner

Answer 15

40 times

Question 16

Low-power

Answer 16

100 times

Question 17

High-power

Answer 17

400 times

Question 18

Resolution

Answer 18

Fine tuning of the image and is done using the fine adjustment knob

Question 19

Electron Microscope

Answer 19

Uses a beam of electrons in a vacuum (no air) as its source
Produces a three-dimensional image
Can magnify thousands/millions of times
Types: SEM – Scanning Electron Microscope
TEM – Transmission Electron Microscope

Question 20

Eyepiece

Answer 20

Contains a lens that magnifies about 10x

Question 21

Arm

Answer 21

Supports the body tube

Question 22

Course Adjustment Knob

Answer 22

Moves the stage slightly to adjust the image

Question 23

Fine Adjustment Knob

Answer 23

Moves the stage slightly to adjust the image

Question 24

Base

Answer 24

Supports the slide being used

Question 25

Light Source

Answer 25

Protects or reflects light upward through the diaphragm

Question 26

Diaphragm

Answer 26

Controls the amount of light passing through the opening of the stage

Question 27

Stage

Answer 27

Supports the slide being used

Question 28

Stage Clips

Answer 28

Holds the slide in place

Question 29

Revolving Nosepiece

Answer 29

Holds the low-power and high-power objective lenses; allows the lenses to rotate viewing

Question 30

Body Tube

Answer 30

Separates the eyepiece lens from the objective lens