Today’s Data Here

• Objective Here!

Brainteaser

• I am the beginning of sorrow, and the end of sickness. You cannot express happiness without me, yet I am in the midst of crosses. I am always in risk, yet never in danger. You may find me in the sun, but I am never seen out of darkness.

Bell Work

• The process by which organisms keep their internal conditions fairly constant is calledA. homeostasis.

B. metabolism.

C. evolution.

D. photosynthesis.

Let’s Review

• What are the characteristics of living things?

Cell Structure & Function

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

Who saw them first?

• Robert Hooke in 1665, was the first person to use the word "cell" to identify microscopic structures when he was describing cork.

Who built the first microscope?

• Anton Van Leeuwenhoek - Father of Microbiology

• made over 500 "microscopes," of which fewer than ten have survived to the present day.

• First to record microscopic observations of muscle fibers, bacteria, spermatozoa and blood flow in capillaries

Background

• Matthias Schleiden ( 1830’s) All plants are composed of cells.

• Theodor Schwann (1831) All animals are made of cells.

• Rudolf Virchow (1858) - Found that • every cell comes from a pre-existing cell.

Cell Theory

• All organism are made up of cells

• A cell is the structural and functional unit of organs and ultimately, organisms.

• Cells are capable of self – reproduction and cells come only from pre-existing cells

What is a Cell

A cell is the smallest unit that is capable of performing life

functions.

Two Types of Cells

Prokaryotic Eukaryotic

NucleusNo nucleus

Examples of Prokaryotic Cells

Salmonella

E. Coli

Meningitis

Sprillum volutans

Bacillus or rod shape

Sprillum or spiral shape

Coccus or circle shape

Prokaryotic/Bacterial Cell

• Do not have structures surrounded by membranes

• Few internal structures

• One-celled organisms, Bacteria

http://library.thinkquest.org/C004535/prokaryotic_cells.html

Parts of the Prokaryotic Cell

• Flagellum – move the bacterium in a fluid medium • Cytoplasm – a semifluid medium that make up the

majority of the cell• Ribosomes – synthesis of proteins• Nucleiod – where the DNA is located• Capsule – gelationous sheath called a slime layer

that surrounds the cell wall• Cell Well – gives the cell its shape• Plasma Membrane – regulates the movement of

molecules into and out of the cytoplasm.• Plasmid – external single DNA molecule

Flagellum and Pili

• Very thin appendages that rotate like propellers to move the cell

• Pili allows the bacteria to stick to other bacteria and surfaces

Cytoplasm• This gel matrix is also

known as protoplasm, and consists of water, enzymes, nutrients, wastes, gases and cell structures. It is the location of growth, metabolism, and replication.

Ribosomes

• synthesis of proteins

Nucleiod

• where the DNA is located

Capsule

• a slime layer that surrounds the cell wall

Cell Wall• gives the cell its shape

Plasma Membrane

• Controls the movement of materials into and out of the cell.

Let’s Practice!

• http://foxbiology.com/ib_review/cells/prokaryotic/intro.html

The whip-like structure on this organism is MOST LIKELY

A. excreted waste products.

B. an organelle for absorbing food.

C. used for locomotion.

D. an adaptation for defense.