Plant and Animal Cells

Cell Scientists

Hans and Zacharias Janssen

• Dutch lens grinders, father and son • produced first compound microscope (2 lenses)

Robert Hooke (1665) English Scientist

• looked at a thin slice of cork (oak cork) through a compound microscope

• observed tiny, hollow, room like structures • called these structures 'cells' because they reminded

him of the rooms that monks lived in • only saw the outer walls (cell walls) because cork cells

are not alive

Anton van Leeuwenhoek (around the same time as Hooke 1680?)

• Dutch fabric merchant and amateur scientist • looked at blood, rainwater, scrapings from teeth

through a simple microscope (1 lens) • observed living cells; called some 'animalcules' • some of the small 'animalcules' are now called bacteria

Matthias Schleiden (1838)

• German botanist

• viewed plant parts under a microscope

• discovered that plant parts are made of cells

Theodor Schwann (1839)

• German zoologist

• viewed animal parts under a microscope

• discovered that animal parts are made of cells

Rudolph Virchow (1855)

• German physician

• stated that all living cells come only from other living cells

The Cell Theory

1. All living things are made up of cells.

2. Cells are the smallest working units of all living things.

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

Definition of a Cell

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

Two types of Cells

• Prokaryotic

• Eukaryotic

Eukaryotic and Prokaryotic • Cells come in two basic types, prokaryotic and eukaryotic.

• "Karyose" comes from a Greek word which means "kernel," as in a kernel of grain.

• In biology, we use this word root to refer to the nucleus of a cell.

"Pro" means "before," and "eu" means "true," or "good."

• "Prokaryotic" means "before a nucleus," and"eukaryotic" means "possessing a true nucleus."

• Prokaryotic cells have no nuclei, while eukaryotic cells do have true nuclei.

Prokaryotic

• Do not have structures surrounded by membranes

• Few internal structures

• One-celled organisms, Bacteria

Eukaryotic• Contain organelles

surrounded by membranes

• Most living organisms

“Typical” Plant Cell

“Typical” Animal Cell

CELL PARTS

Cell Parts- • Organelles Surrounding the Cell- Cell Wall• Most commonly found in plant cells &

bacteria• Supports & protects cells

Cell Membrane

• Outer membrane of cell that controls movement in and out of the cell

• Double layer

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