Eukaryotic Cell  More complex structure  Can be either multi or single celled  Contains a nucleus -Largest organelle -Command Center of the cell -DNA/RNA Cellular Structure and Function Cell Discovery and Theory The McGraw-Hill Companies, Inc./Al Telser, photographer Section 1

Eukaryotic Cell continued…  Contains membrane-bound organelles –Each separate organelle carries out a specialized function  Contains a plasma membrane  Ex: animal, plant, fungi, protist cells Section 1

Section 2-3 Cellular Structure and function Section 2

Cellular Structure and Function Animal Cell Plant Cell Plant and Animal Cell Structures Structures and Organelles Section 3

Plasma Membrane  Thin, flexible boundary between the cell and its environment  Found in both plant and animal cells The Plasma Membrane Cellular Structure and Function Section 2

Selective Permeability Cellular Structure and Function  Controls the amount of a substance entering the cell (nutrients)  Controls the amount of a substance leaving the cell (waste)  2 ways in and out: 1.Directly through tiny pores 2.Protein passageways The Plasma Membrane Section 2

 The plasma membrane is composed of the phospholipid bilayer. Cellular Structure and Function  Hydrophilic head  Hydrophobic tail The Plasma Membrane Section 2

Cellular Structure and Function Section 2

Organelles that control cellular functions (little organ)  Nucleus- largest organelle. Called cell manager or command center of cell. -Nuclear envelope: outer 4 layers of the nucleus. Contains pores so materials can pass b/w nucleus and cytoplasm -DNA: (Deoxy ribonucleic acid) found inside of the nucleus & is the master protein prod. -Chromatin: long strands of DNA that form chromosomes during mitosis & meiosis ( Cell reproduction) -Nucleolus & Ribosomes: nucleolus sm/dense region inside nucleus and produces ribosomes. Ribosomes assemble proteins. Section 2

Assembly, Transport & Storage  Cytoplasm- jelly-like fluid inside the cell. Surrounds all organelles. Most assembly & storage of proteins occurs here.  Endoplasmic Reticulum- series of highly folded membranes. Synthesizes lipids and acts as a transportation system b/w the nucleus & cytoplasm  2 types: Smooth no ribosomes Rough has ribosomes for protein synth. *Ribosomes synth. Proteins. Found in 3 places: nucleus, cytoplasm and ER Section 3

Structures for Storage  3 Main Places for Storage: 1.Golgi Apparatus 2.Vacuoles 3.Lysosomes Section 3

Golgi Apparatus  Series of closely stacked, flattened membranes  Function: it receives the newly made proteins & lipids. G.A. may modify these, it then sorts & packages them to be distributed to the P.M. or other organelles  Proteins get pinched off & enclosed in packages called vesicles, then mod. & shipped to their final destination. Section 3

Vacuoles  Used for temporary storage of:  Food  Enzymes  Waste products  Excess H 2 O  Any other materials needed by the cell *Plants have 1 large vacuole Section 3

Lysosomes  “suicide sacs”  Function: contain enzymes to digest excess or worn out cell parts, food particles, or invading viruses & bacteria *Enzymes do not digest the cell’s proteins because of a protective membrane. Section 3

 What relationship do lysosomes sometimes share w/ vacuoles?  When might a lysosome digest the the cell that contains it? Section 3 Lysosomes cont.… Lysosome will sometimes fuse w/ a vacuole to dispense its enzymes into the vacuole to digest the vacuole's contents. Ex. Lysosomes will digest the tail of a tadpole. The digested parts can then be used to form the legs.

Energy Transformers Mitochondria- plants and animals Chloroplast- plants Section 3

Mitochondria  Structure: this is an organelle made of 2 layers. The inner layer is ly folded  Function: break down food molecules to release E & produce E storing molecules called ATP Section 3

Structures for support and Locomotion  Cytoskeleton  Cilia & Flagella Section 3

Cytoskeleton  Support system of cell. Composed of tiny rods & filaments  Rods & filaments would be analogous to our bones  Structure: 1. tiny hollow rods- microtubules 2. tiny solid filaments- microfilaments  Function: supports the cell and give it shape. Section 3

Cilia  Short, numerous projections that look like hairs  Many/cell  Beat like the stadium “wave” Cellular Structure and Function Flagella  Longer hair-like and less numerous than cilia (1-2 / cell)  Create movement with a whiplike motion Structures and Organelles Section 3

Cellular Structure and Function Structures and Organelles Section 3

Cellular Organization  Cell are the basic unit of organization of an organism  Single celled organism= unicellular  Ex. Bacteria, amoeba, protists  Many celled organism= multicellular  Ex. plants and animals Section 3

 Tissue: group of cells that have similar function  Ex. Muscle tissue, nervous tissue  Cell junctions: sites where cells in a tissue are linked together 3 Functions: 1. cell to cell communication 2. anchor the cells together 3. maintain diff. in the internal envir. of adjacent cells Cellular Organization Section 3

 Organ: group of 2 or more tissues that preform a particular function.  Ex. Heart, lungs, brain  Organ system: group of two or more organs working together to carry out a major life process  Digestive system, circulatory system.  Organism: all organ systems together make up an organism- single living thing Cellular Organization Section 3