The Cell

The Characteristics of
Cells

Lesson 1 / Unit 1

Use your creative mind

Draw what you think a cell would look like.

Draw

Draw what you think a cell would look like.

What a cell really is...

Definitions:

1. The word prokaryote is etymologically composed of the

prefix pro- which means "before" and karyo which refers
to "nucleus", therefore, the prokaryotic cell is considered
prior to the cell that has a cell nucleus or eukaryotic cell.

2. The word eukaryote derives from the Greek eukayron,

composed of eu- (true), and karyon (nucleus), and means
'true nucleus'.

Definitions:

❖cell - is the smallest functional and structural unit of all

living organisms.

❖organism - is any living thing. All organisms are made

up of cells. Some organisms are just one cell.

❖organelle - a small body in the cytoplasm, which

performs a specific function within the cell.

Multiple Choice

The smallest unit of all living organisms.

• organism

• karyote

• cell

• DNA

Multiple Choice

The prefix pro- which means:

• after

• center

• before

• nucleus

Multiple Choice

The prefix eu- which means:

• after

• nucleus

• before

• true

Multiple Choice

A small body that contains all the cells to perform specific functions.

• organism

• DNA

• organs

• organelle

Multiple Choice

Organism is any thing. All organisms are just one cell.

• True

• False

Cell Theory Scientists:

❖Robert Hooke (1665) - first person to describe cells.

He built a microscope to observe small particles.

❖He looked at a thin piece of cork from the bark of a

cork oak. The cork looks like it's made of little boxes.
Hooke called these boxes cells, which means "small
rooms" in Latin.

Cell Theory Scientists:

❖Anton van Leeuwenhoek (1673)- was the first person to describe living

cells when he observed them in a drop of water under a microscope.

❖Matthias Schleiden (1838) - concluded that plants are made of cells.

❖Theodor Schwann (1839) - determined that all animal tissues are made of

cells. He concluded that all organisms are made up of one or many cells.
He also determined that the cell is the basic unit of all organisms. This
scientist wrote two parts of the cell theory.

❖Rudolf Virchow (1858)- proposed that cells could be created or formed

from the division of other cells. He wrote the third part of the cell theory.

What is the cell theory?

❖They are important and key discoveries of
several scientists about the cell.

❖They are essential for the study of organisms,
medicine, biology, etc.

Open Ended

The cell theory lists three basic characteristics of all cells and

organisms:

Three basic characteristics of all cells and organisms:

❖All organisms are made of one or many cells.

❖The cell is the basic unit of every organism.

❖All cells come from existing cells.

Draw

True or False

100 trillion
microorganisms
10 trillion human
cells

Fact: