Chapter 1- Cell theory

Question 0

What is the Cell theory?

Answer 0

All living things consists of one or more organized structures that are called cells or of products of cells.

Question 1

Who discovered cells?

Answer 1

Cells were first identified and named by Robert Hooke in 1665

Question 2

What do microscopes do?

Answer 2

Microscopes give an enlarged view of small cells and the structures they contain, and make it possible for us to examine cells with great detail.

Question 3

Who discovered the nucleus in a cell?

Answer 3

Robert Brown discovered and named the nucleus in the cell in 1831.

Question 4

When did the cell theory arise?

Answer 4

In the mid 1800s

Question 5

What is the unit of measure often used for cells?

Answer 5

Micrometer µm

Question 6

What is a cell?

Answer 6

A cell is the basic functional and structural unit of all living things.

Question 7

Life span of cells

Answer 7

Cells in multicellular organisms do not necessarily live as long as the organism itself. Some cells have a relatively short life span and are constantly being replaced.

Question 8

What are the two different types of microscopes?

Answer 8

Light and Electron

Question 9

What are the different types of light microscope?

Answer 9

Simple light microscope
- compound light microscope
Phase contrast microscope
Fluorescence microscope
Scanning confocal microscope
PlasDIC microscope

Question 10

Different kinds of Electron microscope

Answer 10

Transmission electron microscope

Scanning electron microscope

Question 11

Simple light microscopes

Answer 11

• they use glass lenses
• these are early light microscopes with only one lens
• similar to a magnifying glass

Question 12

Compound light microscope

Answer 12

• at least two sets of lenses; objective and ocular lenses

- most CLM have several objective lenses, each with a different magnification

Question 13

What is the highest magnification obtained with a CLM?

Answer 13

Oil immersion objective lens

Question 14

What do light microscopes reveal?

Answer 14

Details about the arrangement of the cells and the internal structure of cells

Question 15

What can staining do to cells under LM.

Answer 15

Staining or adding fluorescent light can make the cytoskeleton and mitochondria seen under the LM.

Question 16

What is easily seen or shows up nicely under LM?

Answer 16

• plant cells
• chloroplasts easy to see because its green
• cells can be alive

Question 17

Phase contrast microscope

Answer 17

Is a modified compound light microscope that was developed to observe unstinted, intact living cells.

• these microscopes use the fact that different cells transmit and change the direction of light varying degrees and enhance that difference,
• the images produced has highly contrasting bright and dark areas

Question 18

Fluorescent microscope

Answer 18

• is another kind of CLM

- uses UV to reveal compound that have been stained with fluorescent dyes that bind to particular compounds in the cell

Question 19

In a Fluorescent microscope, what does green and red symbolism?

Answer 19

Green- Live

Red- Dead

Question 20

Why are the colors red and green in a fluorescent microscope?

Answer 20

Used to label specific organelles, surface structures, live vs dead bacteria and even ions that move in and out of the cells.

Question 21

What does a transmission electron microscope use instead of light?

Answer 21

It uses a beam of electrons with a much shorter wavelength

Question 22

Instead of glass lenses, what does a TEM use?

Answer 22

TEM has a series of electromagnets that each create an electromagnetic field to control the path of the electron beam

Question 23

What are TEMs able to reveal?

Answer 23

They can look at what’s inside a cell( complex internal structure of a cell), such as the organelles.

Question 24

When was the Scanning Electron microscope released?

Answer 24

1965

Question 25

What must the cells be in order to view them in SEM?

Answer 25

Cells cannot be living, must be dead cells or organisms.

Question 26

What can be achieved with a SEM?

Answer 26

• can get a 3D picture

- provide detailed images of surfaces.