Download Cells * The building blocks of life

CELLS – THE BUILDING BLOCKS OF
LIFE
CELL THEORY – THE HISTORY BEHIND IT
The cell was discovered by Robert Hooke in 1665
He looked at a piece of cork under a microscope and
noted that it looked like honeycomb
In 1674 Anthony van Leeuwenhoek saw the first living
cells using a compound microscope
CELL THEORY
 All living things or organisms are made of cells
New cells are created by old cells dividing into two
Cells are the basic building blocks of life
MODERN CELL THEORY
1. The cell is the fundamental unit of structure and function in living
organisms.
2. All cells arise from pre-existing cells by division.
3. Energy flow (metabolism and biochemistry) occurs within cells.
4. Cells contain hereditary information (DNA) which is passed from
cell to cell during cell division.
5.
MODERN CELL THEORY CONTINUED
5. All cells are basically the same in chemical composition in organisms of
similar species.
6. All known living things are made up of one or more cells.
7. Some organisms are made up of only one cell and are known as unicellular
organisms.
8. Others are multicellular, composed of a number of cells.
9. The activity of an organism depends on the total activity of independent
cells.
VIEWING CELLS – MICROSCOPY
COMPOUND MICROSCOPES
FLUORESCENT MICROSCOPES
CERTAIN PROTEINS WILL FLUORESCE
ELECTRON MICROSCOPES
TYPES OF CELLS
Prokaryotic – simple cells, DNA is not contained, no organelles
Ex: bacteria
Eukaryotic – more complex cells, DNA is contained, organelles
Ex: animal cells and plant cells
EUKARYOTIC CELLS - ORGANELLES
CELL MEMBRANE
A phospholipid layer that allows transport into and out of a cell
NUCLEUS
The control center for the cell
Contains DNA
Surrounded by a double membrane
ENDOPLASMIC RETICULUM
Allows for transport within the cell
Rough E.R – has ribosomes, makes protein
Smooth E.R- has no ribosomes, makes lipids (fats)
Ribosome: Site of protein sysnthesis
GOLGI APPARATUS
Packages, stores and delivers proteins
LYSOSOMES
Clean the cell and destroy worn out cell parts
MITOCHONDRIA
Powerhouse of the animal cell – where cellular respiration occurs
CHLOROPLAST
Found in plant cells only
Site of photosynthesis
Clorophyll gives the plant a green color
CELL WALL
Thick outer layer protecting plant and bacterial cells
VACUOLES
Storage of water, nutrients (food), waste
Plants generally have one large vacuole while animal cells have
several smaller vacuoles
MOVEMENT ACROSS THE CELL MEMBRANE
STRUCTURE OF THE MEMBRANE
Made of
Phosopholipids – provide a barrier from things entering and
leaving the cell
Fatty acids – maintains shape
Proteins – serve as a gate way to allows things in and out of the
cell
http://www.phschool.com/science/biology_place
/biocoach/biomembrane1/regions.html
MEMBRANE ANIMATION
DIFFUSION/OSMOSIS
Movement of molecules across the membrane from high concentrations to less
concentrations
TERMS
Isotonic – two solutions with the same concentration
Hypertonic – a solution with a higher concentration than another
Hypotonic – a solution with a lower concentration than another
FACILITATED DIFFUSION
Movement of molecules from areas of more concentration to less
concentration using proteins
Used with larger molecules
ACTIVE TRANSPORT
Movement of molecules from areas of lower concentration to higher
concentration using proteins
Requires energy!
TERMS
Endocytosis - Transport into the cell using a vesicle
Phagocytosis – transport into the cell using a vesicle that is
destroyed by lysosomes
Exocytosis – Tr
Video: https://www.youtube.com/watch?v=DuDmvlbpjHQansport
out of the cell using a vesicle
Animation:
http://life9e.sinauer.com/life9e/pages/06/062003.html
CELL DIVISION: MITOSIS VS MEIOSIS
CANCER – WHEN CELLS GO WILD!