Post on 13-Jan-2016
Biology
The Study of Living Organisms
What is Living? Use Energy
Metabolism Develop and Grow Homeostasis
Maintain themselves Reproduction
Asexual – reproduction by yourself Sexual reproduction
Evolve Made of Cells
Macromolecules
Large molecules made of smaller molecules linked together
Four Major Types: Protein Carbohydrates Lipids Nucleic Acids
Macromolecules
Protein Subunit: amino
acids 20 amino acids in
living organisms Skin, hair,
feathers, insulin, hemoglobin, antibodies, enzymes
Macromolecules
Carbohydrates Subunits: Saccharides (sugars) Starch, glycogen, cellulose
Macromolcules
Lipids Fatty acid + carboxyl group Used for long term energy storage Fats, oils
Macromolecules
Nucleic Acids Subunit: Nucleotide DNA and RNA Store Genetic Information
The Cell TheoryThe Cell Theory
Some Random Cell FactsSome Random Cell Facts
The average human being is The average human being is composed of around 100 Trillion composed of around 100 Trillion individual cells!!!individual cells!!!
It would take as many as 50 cells to It would take as many as 50 cells to cover the area of a dot on the letter “cover the area of a dot on the letter “ ii””
WOW!!!WOW!!!
Discovery of CellsDiscovery of Cells
Robert Hooke (1665)Robert Hooke (1665) Discovered cells while looking at a thin slice of Discovered cells while looking at a thin slice of
corkcork.. He described the cells as He described the cells as tiny boxes tiny boxes He thought that cells only existed in plantsHe thought that cells only existed in plants
Anton van LeuwenhoekAnton van Leuwenhoek
1673- Observed single-celled organisms in 1673- Observed single-celled organisms in pond waterpond water
He called them “animalcules”He called them “animalcules” The cells were The cells were livingliving
Therefore, it was knownTherefore, it was known
that cells are found that cells are found
in animals as well as plantsin animals as well as plants
Spirogyra
Development of Cell Development of Cell TheoryTheory
1838- Matthias 1838- Matthias SchleidenSchleiden, concluded that , concluded that all all plant parts are made of cellsplant parts are made of cells
1839- Theodor 1839- Theodor SchwannSchwann, stated that , stated that all all animal tissues are made of cells.animal tissues are made of cells.
Development of Cell Development of Cell TheoryTheory
1858- Rudolf 1858- Rudolf VirchowVirchow (physician) found (physician) found that that cells must arise from preexisting cells must arise from preexisting cells cells while studying disease.while studying disease.
The Cell TheoryThe Cell Theory
HAS 3 PARTS:HAS 3 PARTS:1. All organisms are composed of one or 1. All organisms are composed of one or
more cells. (Schleiden & Schwann)more cells. (Schleiden & Schwann)
2. Cells are the basic units of structure and 2. Cells are the basic units of structure and function in an organism. (Schleiden & function in an organism. (Schleiden & Schwann)Schwann)
3. Cells come only from the reproduction of 3. Cells come only from the reproduction of existing cells. (Virchow)existing cells. (Virchow)
Two Types of Cells
1. ProkaryotesFirst living cellsBacteria and ArchaeaNo organellesNo nucleus
2. EukaryotesAnimals and PlantsOrganellesNucleus
Prokaryotic or Eukaryotic?Prokaryotic or Eukaryotic?
Cell Parts
Membrane and Wall
Genetic Material Organelles
Structures that perform specific functions in the cell
Cell Membrane
Selectively permeable phospholipid bilayer Found in prokaryotes and eukaryotes
Nucleus
Nickname: “The Control Center” Function: holds the DNA
Mitochondria
Nickname: “The Powerhouse” Function: Energy formation
Breaks down food to make ATP– ATP: is the major fuel for all cell
activities that require energy
Mitochondria
Mitochondrial DNA Ancient Eukaryotic cell ate a
prokaryotic cell
Ribosomes
Function: makes proteins out of Amino Acids
Found in all cellsprokaryotic and
eukaryotic have different types
Endoplasmic Reticulum 2 Types:
1.Rough ER: – Ribosomes on surface– Function: helps make proteins and
phospholipids
Endoplasmic Reticulum 2 Types:
2. Smooth ER:– NO ribosomes– Function: makes fats or lipids, breaks
down drugs
Golgi Apparatus
Nickname: The Post Office Function: packages, modifies, and
transports materials to inside/outside of the cell
Lysosomes
Nickname: “Clean-up Crews” Function: Digest food particles,
waste, cell parts, and foreign invaders
Have lower pH and special enzymes
Cytoskeleton
Gives Cells Shape and Support Microtubules Intermediate Filaments Microfilaments
Cilia and Flagella
Both help with cell movement
Cilia•Short
•Hairlike
•numerous
Flagella•Long
•One or two per cell
What do Plant Cells Have?
1. Cell Wall2. Vacuole3. Chloroplasts
Pine Needle
Plant Cell
Cell Wall Outside of plasma membrane Made of cellulose
Plant Cell Vacuole
Stores water, waste, enzymes Can make up 90% of plant cell
volume Causes plant to stand upright
Plant Cell Chloroplasts
Make carbohydrates from CO2 and H2O using light energy
Contain Thylakoids with chlorophyll
Animal Cell vs. Plant Cell
Cell Membrane
Hydrophobic and Hydrophilic Membrane Proteins
Communication Join cells together Control transport across membrane
Carbohydrates Allow cells to recognize each other
Fluid Mosaic Model Phospholipids and proteins can slide
past each other
Transport Across Membrane
Diffusion Tendency of molecules to move from
high concentration to low concentration
Osmosis Diffusion of water
Works for small hydrophobic molecules
Transport Across Membrane
Facilitated Diffusion Ions and large
molecules cannot pass freely across the membrane
Carrier proteins Allow molecules to move
down the concentration gradient
NO ENERGY NEEDED! Passive Transport
Transport Across Membrane
Active Transport Carrier proteins move molecules
AGAINST the concentration gradient Requires energy
Transport Across Membrane
Endocytosis Portion of membrane folds inward and
pinches off
Transport Across Membrane
Exocytosis Vesicle fuses with membrane and
dumps contents outside
Cell SizeCell Size
Most cells are 10 to Most cells are 10 to
50µm in diameter 50µm in diameter
Prokaryotes are typically smaller than eukaryotes
YUM….You’re eating an entire cell!
Cell SizeCell Size
The ratio of the surface area to the The ratio of the surface area to the volume limits cell sizevolume limits cell size
Which increases faster, surface Which increases faster, surface area or volume?area or volume?
Why would having a low surface area to volume ratio be important?
Cell ShapeCell Shape
Different cells have different Different cells have different shapes based on functionshapes based on function