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. Maintain Homeostasis

Cell Theory

1. All living things are made up of cells.

2. Basic unit of structure and function of all living things.

3. Cells come from preexisting cells through cell division. cell

Cell Structure & Function

http://koning.ecsu.ctstateu.edu/cell/cell.html

Examples of Cells

Amoeba Proteus

Plant Stem

Red Blood Cell

Nerve Cell

Bacteria

Fibroblasts

Erythrocytes

Epithelial cells

(d) Cell that fights disease

Nerve cell

Fat cell

Sperm

(a) Cells that connect body parts, form linings, or transport gases

(c) Cell that storesnutrients

(b) Cells that move organs and body parts

(e) Cell that gathers information and control body functions

(f) Cell of reproduction

SkeletalMusclecell

Smoothmuscle cells

Macrophage

Over 200 different types of human cells

Generalized Cell

• 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

An organism whose cells lack a true nucleus and Some other cell structures.

Prokaryotic

• Do not have structures surrounded by membranes

• Few internal structures

• EX: Bacteria http://library.thinkquest.org/C004535/prokaryotic_cells.html

Unicellular = one Celled

http://www.wiley.com/legacy/college/boyer/0470003790/animations/cell_structure/cell_structure.htm

Eukaryotic Cell - plantMulticellular = Many cells

Eukaryotic Cell - animal

Multicellular = Many cells

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 Walla 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

Chromosomes

• In nucleus• Made of DNA• Contain

instructions for traits & characteristics

http://library.thinkquest.org/12413/structures.html

A rod-shaped cellular structure made of condensed chromatin

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