Download Lesson 7 – Exploring Cells Cell Theory

Lesson 7 – Exploring Cells
Early Cell Pioneers
Robert Hooke was the first to describe the cell.
When he looked at a slice of cork under his
microscope Hooke used the word “boxes” or
“cell” to describe what he saw. Other early
scientists that helped in the description of cell
theory include Leeuwenhoek, Dutrochet,
Dujardin, and Schleiden.
Lesson 7 – Exploring Cells
Cell Theory
1. Every living organism is made of one or more cells.
2. The cell is the basic unit of structure and function. It is
the smallest unit that can perform life functions.
3. All cells arise from pre-existing cells.
Types of Cells
Prokaryotic Cells
The simplest cells are called Prokaryotic Cells.
These cells do not have a membrane-bound
nucleus and are very small. Cells in the Kingdom
Monera such as bacteria and cyanobacteria are
examples of prokaryotic cells.
Types of Cells
Eukaryotes
These more complex cells are known as
eukaryotic cells. They have a membrane-bound
nucleus as well as organelles that carry out the
life functions of the cells. Examples of eukaryotic
cells can be found in organisms within the
Kingdoms; Anamalia. Plantae, Protista, Fungi.
Lesson 7 – Exploring Cells
Parts of a Cell
• Organelle – “Little Organ” One of many
structures in a cell that performs a specific
function.
• Cell Membrane – (plasma membrane) Living
membrane that separates the cell from the
rest of the environment and helps control the
passage of substances into and out of the
cell.
Lesson 7 – Exploring Cells
• Nucleus – “Command Central” regulates all of
the activities that take place in the cell.
• Chromosomes – where information for the
cells activities are stored. Located in the
nucleus.
• DNA – (deoxyribonucleic acid) carries the
hereditary traits that are passed from parent to
offspring. Stored in the chromosomes.
Lesson 7 – Exploring Cells
• Cytoplasm – a jelly-like substance that lies
between the cell membrane and nuclear
envelope.
• Mitochondria – “powerhouse” of the cell where
nutrients are broken down to be used or stored
for future use.
• Ribosomes – help make the proteins the cell
needs to function.
Lesson 7 – Exploring Cells
• Endoplasmic reticulum – (ER for short) a
series of cavities connecting the nuclear
envelope to the cytoplasm that some
substances use for travel between the two.
• Golgi bodies – package the proteins that are
made by the ribosomes to be sent out of the cell.
• Lysosomes – help the cell process
proteins.
Lesson 7 – Exploring Cells
• Vacuoles – filled with water, food, or waste,
they are the cell’s storage tanks.
• Cell Wall – (plant) found in a plant cell. A
non-living rigid outer layer that contains
cellulose. Supports and protects the cell.
• Plastids – (plant) contain pigments that give
parts of plants their characteristic color. Red
for tomatoes or orange for carrots.
Lesson 7 – Exploring Cells
• Chloroplast – (plant) found in the leaves and
stems. Contain chlorophyll which the plant
uses to produce food through the process of
photosynthesis.
• Vacuoles – in plants these are much larger.
Most plants have a large central vacuole that
helps to support the plant and serves as a
storage place for water, sugar, starch, and
proteins.
Lesson 7 – Exploring Cells
Video (20 minutes)
Cells – The Basic Unit of Life
Reference
www.historyforkids.org
http://library.thinkquest.org/C004535/different_cell_types
.html
http://www.biologycorner.com/lesson-plans/cells/
Prentice Hall Biology, 5th Edition
Textbook, “Organisms – From Macro to Micro