Chapter 5: Cell Structure and Function
5-1: The Cell Theory
The Cell Theory
All living things are made of ______
Cells are the basic units of structure and function in living things
______, a Dutch biologist, was the inventor of the microscope
oEnabled him to see things that no one had ever seen before
The Cell Theory
Van Leeuwenhoek’s work interested other people
o______examined slices of cork
oSaw that it was composed of thousands of tiny chambers
oCalled these chambers ______
Over the next 200 years, other scientists began to discover that cells were not only found in plants but in other living things too
o______—1833—discovered the nucleus
o______—1838—stated that all plants are made of cells
o______—1839—all animals are made of cells
o______—1855—all cells arise from preexisting cells
The observations of these scientists are summarized into the ______
o______
o______
o______
Chapter 5: Cell Structure and Function
5-2: Cell Structure
Cell Structure
Enormous variety in the ______and ______of cells
Despite differences in size and shape, there are certain structures that are common to most cells
The cells of animals, plants, and related organisms have three basic structures: ______, or boundary of the cell; ______, or control center; and ______, or material between the cell membrane and the nucleus
Cell Membrane
All cells are separated from their surroundings by a ______
______
oRegulates what enters and leaves the cell
oAids in protection and support of the cell
It must communicate with other cells, take in food and water, and eliminate wastes
Composed of several kinds of molecules
o______
o______
o______
Cell Wall
In organisms such as plants, algae, and some bacteria, the cell membrane is surrounded by a ______
oHelps ______the cell
oVery ______—allows water, oxygen, carbon dioxide, and other substances to pass through
oMade of ______
Nucleus
In many cells we can see a large, dark structure, called the ______
oContains ______
______are organisms whose cells lack nuclei
o______
o______
______are organisms whose cells contain nuclei
oMostly ______
Nuclear Envelope
Surrounding the nucleus are two membranes that form the ______
oForm the boundary around the nucleus
Contains dozens of ______allowing substances to flow in and out of the nucleus
Nucleolus
Most nuclei contain a small region called the ______that is made up of ______
oThe structure in which ______are made
Aid in the production of proteins within the cell
Chromosomes
The DNA in the nucleus of eukaryotic cells is attached to special proteins and forms large structures called ______
oContain the genetic information that must be passed to each new generation of cells
Cytoplasm
The cytoplasm is the area between the ______and the ______
Contains many important structures
Chapter 5: Cell Structure and Function
5-3: Cytoplasmic Organelles
Cytoplasmic Organelles
The structures inside the cytoplasm are generally called ______
An organelle is a tiny structure that performs a specialized function in the cell
oEach organelle has a ______
Mitochondria and Chloroplasts: Power Stations
All living things require ______
The ______and the ______are key organelles that change energy from one form to another
oMitochondria change chemical energy in food into compounds that the cell can use
oChloroplasts trap solar energy and convert it into chemical energy
Mitochondrion
oContains ______special membranes
Outer membrane ______the organelle
Inner membrane has many folds that increase the ______of the mitochondrion
Chloroplast
oFound only in ______and ______
o______membranes
Two envelope-like membranes
Third membrane where the sun’s energy is changed into chemical energy
Ribosomes: Protein Factories
______are the structures in which proteins are made
oMade of RNA and protein
oSome are ______to membranes; some are found ______in the cytoplasm
oAmong the ______organelles
Endoplasmic Reticulum and Golgi Apparatus: Manufacturers and Shippers
Many cells are filled with a complex network of sacs known as the ______, or ______
o______through the inside of the cell
oTwo types:
______—no ribosomes attached
______—ribosomes attached—involved in the synthesis of proteins
Proteins are often modified by special enzymes that attach carbs and lipids to them
In most cases, the proteins are first moved into special compartments known as the ______
oFlattened stack of membranes
oAfter modification, the proteins may then be released from the cell
**The Golgi apparatus modifies, collects, packages, and distributes molecules made at one location of the cell and used at another**
Lysosomes: Cleanup Crews
When a cell encircles a particle, the cell membrane forms a pocket around the foreign material
The foreign material must now be ______, or broken down
o______
Contain ______and ______necessary for digestion
Formed by the ______
Plants cells do not have lysosomes
Vacuoles and Plastids: Storage Tanks
______store materials such as water, salts, proteins, and carbohydrates
______are plant organelles that may take many forms, one of which is the chloroplast
oInvolved in the storage of food and pigments
oExamples:
Leukoplasts—store starch
Chromoplasts—store pigments
Cytoskeleton: Framework
Most cells are capable of some type of movement
______– framework of filaments and fibers that support cell structure and drive cell movement
o______-long, thin fibers that function in the movement and support of the cell
o______-hollow tubes made out of proteins
______