Download Chapter 7 The Cell and its Organelles

Discovery of the Cell
• Invention of the microscope
-Robert Hooke: used a simple
microscope to look at cork in
1665. He called what he saw
“chambers” or “cells”
-Anton van Leeuwenhoek: used
a single lens microscope to
observe pond water and found a
new world of living things.
Cell Theory
• After numerous observations, scientists
compiled their thoughts to form the cell
theory.
• The cell theory states:
1. All living things are composed of cells
2. Cells are the basic structure and
function in living things
3. New cells are produced from existing
cells
Prokaryotes vs. Eukaryotes
• Does it have a Nucleus?
• Nucleus: membrane bound organelle that
contains genetic information (DNA). Controls the
cells activities
• *HINT*
• “U-CARRY-IT” *HAS A NUCLEUS
• Eukaryote *has a nucleus
• Prokaryote *does NOT
Prokaryotes vs. Eurkaryotes
Cells do not contain a
nucleus
Cells contain a nucleus
No membrane bound
organelles
Membrane bound
organelles
DNA is found within (no
specific area)
DNA is found in nucleus
Ex: bacteria
Ex: animal cell, plant cell
Prokaryote
Two Types of Eukaryotes
Eukaryotic Cells
• Eukaryotic cells are divided into two
major parts: organelles and cytoplasm.
• Organelles are “little organs” with
specialized functions.
• Cytoplasm (both) is the major portion of
the cell outside the nucleus.
Nucleus (both)
• Controls most cell
processes
• Contains DNAinstructions for life
• NUCLEOLUS
(both)
– Region inside nucleus
where assembly of
ribosomes begin
Nucleus Con’t
NUCLEAR ENVELOPE (both)
surrounds the nucleus
allows materials to come
in and out
CHROMATIN (both)
Granular material visible within the nucleus;
consists of DNA
Ribosomes (both)
• Produce PROTEINS by following coded
instructions from the nucleus
Endoplasmic reticulum (both)
• 2 Kinds of ER
– SMOOTH= is smooth
– ROUGH=has ribosomes on it **“BUMPY”
• FUNCTIONS:
• Lipid components of the cell membrane are
assembled in the ER.
• The ER is where proteins and other materials
are exported from the cell
Golgi apparatus (both)
• Function: modify, sort, and package
proteins and other materials for
storage or secretion
• Put the “finishing touches” on proteins
before they are ready to leave the
“factory”
Lysosomes (both)
• Filled with digestive enzymes
FUNCTION:
• Break down lipids, carbohydrates, or
proteins or break down organelles that
are no longer useful.
• Clean up the “junk”
Vacuoles (both)
• Sac-like structures
that store materials.
• “Storage bins”
• ***It is very large in
a plant cell
Mitochondria (both)
• “Powerhouse” of the
cells
• Convert chemical
energy stored in
food into compounds
that are more
convient for the cell
to use.
• Key function:
ENERGY or ATP
Chloroplasts (plant only)
• Only found in plants
• Contain chlorophyll
• Capture energy from
sunlight and convert
it into chemical
energy during
photosynthesis
Cytoskeleton (both)
• Network of proteins that helps the cell
maintain its shape.
• Made of Microfilaments and
Microtubules
• In Animal cells there are CENTRIOLES
– They help with cell division