Topic 2: Cells and Cell Processes Cells: Cell Theory 1. 2. 3. **There Are 2 Exceptions to the Cell Theory 1. the First Cell

Topic 2: Cells and Cell Processes

Cells:

Cell Theory 1. 2. 3. **There are 2 exceptions to the Cell Theory

1. The first cell could not come from a previous existing cell 2. Viruses are not made up of cells but they do contain genetic material. Viruses reproduce inside another cell, called the cell.

Organelles: Specialized subunits within the cell that has a specific function

 Cells can be separated into 2 broad categories o o **The average person is made up of approximately 100 trillion cells and 200 different eukaryotic cell types**

Prokaryotic Cells Eukaryotic Cells Both

Theory of Endosymbiosis  Eukaryotic cells containing organelles (like mitochondria and chloroplasts) evolved when free-living prokaryotes took up permanent residence inside other larger prokaryotic cells (about 2 billion years ago)  This became the origin of complex eukaryotic cells leading to the evolution of all multi-celled organisms

Organelle Function Cytoskeleton Proteins that support and shape the cell  Microtubules Make up cilia, flagella and spindle fibers  Microfilaments Made up of actin and help support the shape of the cell Cytoplasm  Fluid like portion  Located between the and the______ Holds the organelles in place

Nucleus  Stores and protects the genetics information (DNA)  Also contains the ______Nucleolus  Responsible for the production of ______Mitochondria  “Powerhouse” of the cell  Supplies ______to the cell through the process of ______ Contain their own DNA and ribosomes Endoplasmic Reticulum  Highly folded organelle  Involved in the production of ______and ______ Two types o Rough ER: ______are attached to the ER o Smooth ER: no ______attached Ribosomes  Responsible for producing ______ Located in the ______or on the ______Golgi apparatus  The UPS of the cell  Modifies, sorts and delivers ______Vacuole  Fluid filled sac  Stores necessary materials for the cell ***Much larger in ______cells than ______cells Chloroplasts  Carry out ______in plant cells  Have their own DNA and ribosomes Cell wall  Strong layer that protects, supports and shapes the cell  NOT found in animal cells Centrosomes  Produces ______ Contains ______ Centrioles: important during cell division and made up of microtubules  ONLY found in ______Lysosomes  Contain enzymes that protect the cell from foreign invaders  Breaks down damaged cell parts Peroxisomes  Contain catalase (which converts hydrogen peroxide into water with the release of oxygen atoms) Cell membrane (plasma  Controls the passage of materials into and out of the cell membrane)  Cell membranes are selectively permeable  Selectively permeable: ______ Consists of a double layer of ______ Phospholipid o Charged phosphate group o Glycerol o 2 fatty acid chains  Fluid Mosaic model: current model showing structure of cell membrane as a phospholipid bilayer with embedded proteins o Cholesterol: strengthens the cell membrane o Proteins: helps transport materials and sends signals across the membrane . Acts as enzymes . Acts as receptors o Carbohydrates: used as an identification marker

Question 1: Label the following organelles

A: F: B: G: C: H: D: I: E:

Cell Communication  Cell membranes secrete molecules and contain carbohydrates on the outside surface that can act as signals to communicate with other cells  Receptor: protein that detects a signal molecule and performs an action in response o The receptor binds to only certain molecules o Two types . Intracellular: protein located within the cell that binds to a molecule that has crossed the cell membrane  Ex:

. Membrane: protein located within the cell membrane that binds to a molecule  Receptor that sends a message to the inside of the cell  Ex: Question 2: Answer the following questions with letters of the appropriate organelles based on the diagram below

a) Organelle that produces proteins and lipids b) Part of the cell membrane composed of a hydrophilic head and hydrophobic tail c) Identification markers found on the outside of the cell membrane d) Embedded protein that allows certain materials to pass into and out of the cell e) Organelles that performs cellular respiration f) Organelle that sorts and ships proteins

Question 3: Organize the following terms from smallest to largest: Cells organ systems tissues Organelles organs organism

     Cell Transport  Concentration: the number of molecules of a substance in a given volume  Concentration gradient: the difference in the concentration of a substance from one location to another

1. Passive transport: no cellular energy is used in order for a particle to cross the membrane i. Particles move from an area of to an area of in order to maintain homeostasis ii. Diffusion: type of passive transport iii. Osmosis: diffusion of through a membrane 1. Water molecules move from a concentration of water to a concentration of water until equilibrium is reached

2. Active transport: process by which molecules use energy ( ) to move the concentration gradient (from concentration to concentration) Types:  Endocytosis: o Pinocytosis: o Phagocytosis: . Ex:  Exocytosis:  Contractile vacuole:

Tonicity: measure of pressure of two solutions separated by a semi-permeable membrane 1. Hypertonic solution: solution in which concentration of solutes is greater than concentration of solutes the cell.  This causes water molecules to move of the cell.  RESULT: 2. Hypotonic solution: solution in which concentration of solutes is less than the concentration of solutes the cell  Water will move the cell  RESULT: 3. Isotonic solution: solution in which concentration of solutes the cell is to the concentration of solutes the cell Question 4: What type of solution was this cell placed in? Explain why this happened.

What functions must an organism carry out in order to be considered living? Life Functions 1. a.

9. Metabolism: Homeostasis: