Cell Structure & Function

Objective 1: Describe the cell’s role as the structure unit.

What is the cell’s roll in an organism?

Cells Are the basic units of life. They are divided into two categories The cell is considered the building block of living organisms. Organisms are grouped by number of cells. –Unicellular: organisms that only have one cell. –Multicellular organisms that are composed of many cells.

Examples of Cells Amoeba Proteus Plant Stem Red Blood Cell Nerve Cell Bacteria

Cell Theory All living things are made up of cells. Cells are the smallest working units of all living things. All cells come from preexisting cells through cell division.

Definition of Cell A cell is the smallest unit that is capable of performing life functions.

Two Types of Cells Prokaryotic Eukaryotic

Prokaryotic Do not have structures surrounded by membranes Few internal structures One-celled organisms, Bacteria

Eukaryotic Contain organelles surrounded by membranes Most living organisms PlantAnimal

Objective 2: Identify the various components of plant and animal cells and explain their function.

“Typical” Animal Cell /~ acarpi/NSC/images/cell.gif

“Typical” Plant Cell

What are the parts of a cell and their function?

Cell Parts Organelles

Surrounding the Cell

Cell Membrane Outer membrane of cell that controls movement in and out of the cell Double layer

Cell Wall Most commonly found in plant cells & bacteria Supports & protects cells

Inside the Cell

Nucleus Directs cell activities Separated from cytoplasm by nuclear membrane Contains genetic material - DNA

Nuclear Membrane Surrounds nucleus Made of two layers Openings allow material to enter and leave nucleus

Chromosomes In nucleus Made of DNA Contain instructions for traits & characteristics

Nucleolus Inside nucleus Contains RNA to build proteins

Cytoplasm Gel-like mixture Surrounded by cell membrane Contains hereditary material

Endoplasmic Reticulum Moves materials around in cell Smooth type: lacks ribosomes Rough type (pictured): ribosomes embedded in surface

Ribosomes Each cell contains thousands Make proteins Found on ribosomes & floating throughout the cell

Mitochondria Produces energy through chemical reactions – breaking down fats & carbohydrates Controls level of water and other materials in cell Recycles and decomposes proteins, fats, and carbohydrates

Golgi Bodies Protein 'packaging plant' Move materials within the cell Move materials out of the cell

Lysosome Digestive 'plant' for proteins, fats, and carbohydrates Transports undigested material to cell membrane for removal Cell breaks down if lysosome explodes

Vacuoles Membrane-bound sacs for storage, digestion, and waste removal Contains water solution Help plants maintain shape

Chloroplast Usually found in plant cells Contains green chlorophyll Where photosynthesis takes place

Activity 1 Objectives: 1. Students will draw a diagram of both the plant cell and animal cell. Page 63 & Students will label the cell and describe each parts purpose and function.

Activity 2 Objectives: 1Using the diagrams and information from activity 1, students will create a compare and contrast diagram on the plant and animal cell. 2. On the back of the diagram answer the discussion questions 1, 2, 3,7, 13, 17 using complete sentences.

Mitosis Objective: 1. What is mitosis and why is it important? 2. What are the steps of mitosis and what happens in each?

Mitosis A sequential process of cell division. At the conclusion of mitosis, what was formerly one cell becomes two. This process is repeated over and over during the life of the organism.

Mitosis Mitosis is cell division for growth and repair. This process involves the division of cells that make up the plant body, which consists of the roots, stem, leaves, and flower parts. This process is continually occurring. With out MITOSIS plant growth could not occur.

Objective 2 Mitosis is divided into four steps. They are: –Prophase –Metaphase –Anaphase –Telophase

Prohase Involves the development of chromosomes. Not replication of DNA This step follows a time of rest for the cell.

Metaphase Is a step in which the chromosomes move to the middle of the cell and line up along the equator of the cell.

Anaphase- 3 rd step Is where the chromosomes separate and move to opposite sides of the cell. Shortening spindle fibers separate the chromosomes.

4 th step- Telophase The nucleus reforms and a membrane appears between each mass of chromosomes. The newly formed membrane divides the cytoplasm. Once this is completed, the two separate cells repeat the process.

Activity 3 Students are going to create a story book that illustrates the life of a reproducing cell. The four phases of mitosis will be step in the cells life. Students will name the cell. Students will explain what happens to the cell during each step of the cells life. Students will use pictures to illustrate the story. Story book due Friday, Feb12th