Structure and Function of Cells State Objective 3.b.

What are Cells?The cell theory states the following:

All living things are composed of cells. Cells are the basic units of structure and

function in living things. All cells are produced from other cells.

Two Types of CellsProkaryotic cells lack membrane-

bound internal structures. Ex. Bacteria

Eukaryotic cells contain membrane-bound structures Ex. Blood cells (plant and animal cells)

Tour of Eukaryotic Cells

Cell WallRigid layer that surrounds the cells of

plants and some other organisms(bacteria) It helps protect and support. Made of strong material called cellulose.

Cell Membrane The cell membrane protects the contents of the

cell and helps control the materials that enter and leave. Allows food and oxygen into the cell and waste

products out of the cell.

Moving Material into & out of CellsCell membranes are

selectively permeable.Two types:

Passive Transport allows materials to pass through the cell membrane without using energy

Active Transport requires the cell to use energy by using transport proteins to move materials across the cell membrane

Cytoplasm A thick, clear, gel-like fluid that fills the regions

between the cell membrane and the organelles of Eukaryotic cells. Organelles are tiny cell structures that carry out specific

functions with-in the cell.

Nucleus The nucleus is the cell’s control center, directing all of

the cell’s activities. Contains DNA Nucleolus makes ribosomes which are small grain-shaped

organelles that make proteins

H2O

Energy Mitochondrion

Known as the “powerhouses” of the cell because they convert energy in food molecules to energy the cell can use to carry out its functions

O₂

Glucose

Chloroplast Green structures typically found in plant cell to make

food by photosynthesis. Captures energy from sun-light and changes it to energy

the cell needs to make food.

Vacuole Type of sac that stores water, food, and other

materials needed by the cell. Vacuoles in plants cell are larger than those in animal

cells.

Vacuole

Comparing Plant and Animal CellsPlant cells have a larger vacuole for more

storage.Plants have chloroplasts for carrying out

photosynthesis.Plants have cell walls for shape & support.

Chloroplast

Mitochondria

Cell Membrane

Golgi Apparatus

Cell Wall

Ribosomes

Cytoplasm

Nucleus

Endoplasmic Reticulum

Lysosome

Vacuole

Click on organelle to activate name (cursor will change for “live” organelles).

Name That Part

Compare a cell to a school. For each organelle, describe something in the school that would perform that same function. Include nucleus, mitochondria, chloroplast, endoplasmic reticulum, lysosomes, vacuole, cytoplasm, cell membrane, cell wall

Types of Cells

Types of Cells Not all cells are the same. Cells with different structures perform

different functions. Both plants and animals have

specialized cells that perform specific functions.

Organization of Life Cells- smallest basic unit of life Tissues- a group of cells that perform a

function Organs- a group of tissues Organ systems- a group of organs Organism

Types of Tissues Epithelial Connective Muscle Nervous

Epithelial Tissue Tissue that covers internal or external

surfaces of an animal’s body They may consist of single or many

layers. Cells are packed tightly together with

little space between. Classified by shape and function. Examples: skin, linings of internal

organs, blood vessels

Squamous Epithelium

Cuboidal Epithelium

Connective Tissue Connects and supports other tissues. Cells are often spaced farther apart. Examples include blood, bone, cartilage,

ligaments, tendons, adipose

Blood Tissue that carries oxygen, nutrients,

removes wastes, and fights infection. Made of red blood cells, white blood

cells, and platelets. Red blood cells contain a protein called

hemoglobin that attaches to oxygen molecules.

Red Blood Cells • Shaped like flattened disks.

• Do not contain nuclei.

• Most numerous cell in the body.

Blood White blood cells can move in and out of

blood vessels to fight infection. Larger but fewer in number than red

blood cells. Body can increase production when an

infection occurs.

White Blood Cells

Blood Platelets are tiny, oval-shaped cells that

help blood form clots. Stick together when blood vessels

break. Are constantly being replaced.

Platelets

Bone A rigid connective tissue made mostly of

calcium. Provides shape and support, protection,

and allow the body to move. Compact bone- hard, strong outer

covering. Spongy bone- mesh-like center of bones

that contains marrow.

Bone

Which is compact? Which is spongy?

Adipose Tissue A loose connective tissue also called fat. Stores energy, cushions and insulates

the body. Found beneath the skin and around

internal organs.

Adipose Tissue

Other Connective Tissues Cartilage is a tough, flexible tissue that

covers the ends of bones. Ligaments are fibrous, slightly

stretching tissues that connect bones at a joint.

Tendons connect muscles to bones and allow movement.

Ligaments, Tendons, and Cartilage

Muscle Tissue Tissues that contract and relax to allow

the body to move. Three types: skeletal, smooth, cardiac Skeletal attaches to bones. Smooth is

found in internal organs. Cardiac is found in the heart.

Skeletal muscle is voluntary and striated (striped).

Muscles

Nervous Tissue Neurons (nerve cells) are the basic unit

of the nervous system. Form the brain, spinal cord, and other

nerves. Controls the body and responds to

stimuli.

Parts of a NeuronCell body- contains nucleusAxon- carries messages from the cell

Dendrite- receives messages from other cells.

Neurons

How Tissues Work Together

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