Cell Structure and Function NC Essential Standards Structure and Functions of Living Organisms Bio.1.1, Bio.1.2 Unit Topics Cell Structure: Eukaryotic vs. Prokaryotic, Plant cells vs. Animal cells, Organelle Structure and Function Cell Function: Organelle Structure and Function, Cell Specialization and Communication, Homeostasis, The Cell Cycle K. Nifong; 2013

Organization of Living Things All living things are organized. CellsTissuesOrgansOrgan SystemsOrganism Why are cells so important?

The Cell Theory

The Cell Theory – 3 Parts! 1. Cells are the basic unit of life! 2. All organisms are made of cells! Building The Cell Theory Anton Von Leeuwenhoek Described cells in pond water looking through a simple microscope Robert Hooke Used compound microscope; studied cork and said it looked like cells Schleiden and Schwann All plants and animals are made of cells! Rudolph Virchow 3. New cells only come from existing cells

Cell type comparisons

PROKARYOTIC EUKARYOTIC Major Cell Types

Major Cell Types No membrane-bound organelles Ribosomes Present PROKARYOTIC EUKARYOTIC No membrane-bound organelles Ribosomes Present No Nucleus Plasmids of circular DNA Smaller Simple Mostly Unicellular Ex. BACTERIA Membrane-bound organelles: mitochondria, chloroplast, nucleus, etc. Ribosomes present Nucleus!!! DNA in nucleus Larger Complex: Specialization! Mostly Multicellular Ex. PLANTS, ANIMALS, FUNGI, PROTISTS Major Cell Types

Eukaryotic Cell Types

Eukaryotic Cell Types PLANT CELLS Chloroplasts Vacuoles – LARGE! photosynthesis Vacuoles – LARGE! Store water, salts, etc. Helps maintain structure of cell wall Cell Wall Provides structural support, rigid ANIMAL CELLS Do not have those 3 structures Why not? (*Animal cells/do have vacuoles – much smaller)

Cell structure and function

Cell Organelles Organelles: small structures within cells that carry out various functions STRUCTURE DETERMINES FUNCTION Surface Area – greater surface area provides for more productivity FOLDS!!!

Organelles Nucleus: houses genetic material Nuclear Membrane/Envelope: surrounds and protects genetic material Nuclear Pores: holes in the nuclear membrane Nucleolus: dense region; ribosomal subunits Chromatin: genetic material Ribosomes: make proteins using genetic information from the nucleus, 2 subunits

Organelles Endoplasmic Reticulum: folded membrane system surrounding nucleus; stores and transmits lipids and proteins throughout cell

Organelles Golgi Apparatus: modifies, prepares proteins and lipids to send out of cell

Organelles Mitochondria: site of cellular respiration; converts food energy (glucose) into cell energy (ATP) Very FOLDED inner-membrane: cristae!

Organelles Chloroplast: site of photosynthesis; converts light energy into glucose PLANTS!

Organelles Lysosomes: break down organic molecules and digest worn-out cell parts

Organelles Vacuole: Storage for water, organic molecules, salts, etc. **Large in plants!

Cell Parts Cytoskeleton: A network of proteins that help cell maintain shape. Microtubules: Thin, hollow cylinders of protein. Microfilaments: Thin, solid protein fibers. Cilia and Flagella: Cilia: Short, numerous, hair-like projections from the plasma membrane of the cell. Often beat synchronously to produce motion. Flagella: Long projections that move in a whip-like motion to produce movement. The major method of locomotion in unicellular organisms. Found mainly in bacteria and Protists Sperm cells!

Structures for Locomotion

Structures for Locomotion

Cytoplasm Fluid-filled space surrounding organelles

Surrounding the Cell Plasma Membrane/Cell Membrane: phospholipid bilayer Fluid mosaic model membrane that surrounds ALL cells Regulates what enters and leaves; Semipermeable! Permeable to lipids, nonpolar and smaller substances Maintains solution concentrations! Contains Transport Proteins Embedded in membrane; help certain substances move into or out of cell

The Plasma Membrane Structure

Surrounding the Cell Cell Wall: made of cellulose, helps maintain structure PLANTS, Fungi, Prokaryotes, Algae