Characteristics of Biotic Factors Made of cells. Consist of levels of organization (cell, tissue, organ, organ system) Respond and adapt to their environment Grow and develop Reproduce - The production of offspring that are similar to the parents. Use energy. Undergo chemical reactions (metabolism) Movement within a cell to maintain Homeostasis Which of these require energy?

Cell Theory pg.395 in txtbk. organ system All living things are made up of cells. Basic unit of structure and function of all living things. Cells come from preexisting cells through cell division. population organism organ system organ tissue cell

Cell Structure & Function http://koning.ecsu.ctstateu.edu/cell/cell.html

Examples of Cells and their different structures Amoeba Proteus Plant Stem Bacteria Red Blood Cell Nerve Cell

Over 200 different types of human cells with different structures Erythrocytes Fibroblasts Epithelial cells (a) Cells that connect body parts, form linings, or transport gases Nerve cell Skeletal Muscle cell Smooth muscle cells (e) Cell that gathers information and control body functions (b) Cells that move organs and body parts Sperm Macrophage (f) Cell of reproduction Fat cell (c) Cell that stores nutrients (d) Cell that fights disease

Generalized Cell Human cells have three basic parts: All cells have some common structures and functions Human cells have three basic parts: Plasma membrane—flexible outer boundary Cytoplasm—intracellular fluid containing organelles Nucleus—control center

Prokaryotic Cells Eukaryotic Cells ~ 1/10 the size of eukaryotic cells Large compared to prokaryotic cells Nuclear area not membrane bound called the nucleoid Membrane bound nucleus w/ a nucleolus Single circular DNA Many chromosomes w/ linear DNA No membrane bound organelles MB: Golgi, lysosomes, ER, peroxisomes, mitochondria

Prokaryotic and Eukaryotic Cells Similarities Both have ribosomes and cytoplasm Both require a supply of energy Both have DNA as their genetic material Both are covered by a plasma (cell) membrane Both are made from the same basic chemicals: carbohydrates, proteins, nucleic acid, minerals, fats and vitamins. Both regulate the flow of the nutrients and wastes that enter and leave them

Prokaryotic Do not have structures surrounded by membranes An organism whose cells lack a true nucleus and Some other cell structures. Do not have structures surrounded by membranes Few internal structures EX: Bacteria Unicellular = one Celled http://www.wiley.com/legacy/college/boyer/0470003790/animations/cell_structure/cell_structure.htm http://library.thinkquest.org/C004535/prokaryotic_cells.html

Eukaryotic Cell - plant Multicellular = Many cells

Eukaryotic Cell - animal Multicellular = Many cells

Organelles – Small cell structures Cell Parts Organelles – Small cell structures

Surrounding the Cell

Cell Membrane All cells contain a cell membrane Controls movement in and out of the cell Double layer http://library.thinkquest.org/12413/structures.html

Cell Wall a rigid layer of nonliving material that surrounds the cells of plants and some other organisms. The outermost structure of the cell Most commonly found in plant cells & bacteria Supports & protects cells http://library.thinkquest.org/12413/structures.html

Inside the Cell

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

A rod-shaped cellular structure made of Chromosomes A rod-shaped cellular structure made of condensed chromatin In nucleus Made of DNA Contain instructions for traits & characteristics http://library.thinkquest.org/12413/structures.html

Cytoplasm Gel-like mixture – 80% water Located between the nucleus and cell membrane Many organelles found suspended within the cytoplasm Cyto = cell Plasm = to form or mold

Endoplasmic Reticulum Transport system - Moves materials to Golgi Smooth type: lacks ribosomes Rough type (pictured): ribosomes embedded in surface http://library.thinkquest.org/12413/structures.html http://www.biology.arizona.edu/cell_bio/tutorials/pev/page3.html

Ribosomes Make proteins Each cell contains thousands - found on ER & floating throughout the cytoplasm http://library.thinkquest.org/12413/structures.html

Mitochondria Produces energy through chemical reactions – THE POWERHOUSE OF THE CELL Controls level of water and other materials in cell Recycles and decomposes proteins, fats, and carbohydrates http://library.thinkquest.org/12413/structures.html

Golgi Bodies Sorts, modifies, stores, packages & distribute materials Move materials within & out of the cell http://library.thinkquest.org/12413/structures.html

Lysosome Transports undigested material to cell membrane for removal Contain digestive enzymes – break down old cell parts, cells, bacteria, and viruses Cell breaks down if lysosome explodes http://library.thinkquest.org/12413/structures.html

Vacuoles Membrane-bound sacs for storage, digestion, and waste removal Contains water solution Help plants maintain shape http://library.thinkquest.org/12413/structures.html

Chloroplast Usually found in plant cells Contains green chlorophyll Where photosynthesis takes place http://library.thinkquest.org/12413/structures.html http://www.wiley.com/legacy/college/boyer/0470003790/animations/cell_structure/cell_structure.htm