Chapter : Chapter 2 and 3 8/27 Reading: Carbon-based Molecules 1 8/30 Date Description of Assignment/notes/ outline/worksheet Page # Homework Stamp 8/27 Reading: Carbon-based Molecules 1 8/30 Ws 2.3 Reviewing Main Ideas 2 * 8/31 Notes Power Notes 2-5 3 Study Guide 2.5 4 9/2 Macromolecule Reading 5 Crossword Puzzle with reading 6 9/1 Lab Enzymes 7 (graded) 9/3 Quiz chapter 2 8 Ch 3.1 Notes Cell Theory 9 Extra stamp 9/7 Study Guide 3.1 and 3.2 10 9/8 Power notes 3-2 11

Section 3-2 “Cell Organelles”

Today’s Objectives – When we finish the notes fill in your answers Describe the internal structure of eukaryotic cells. Skip 1 line (to answer this later) Summarize the functions of organelles in plant and animal cells. Skip 4 lines (to answer this later)

KEY CONCEPT Eukaryotic cells share many similarities like organelles (mini-organs)

Main Idea: Cells have an internal structure.   Eukaryotic cells are highly organized structures. Each has a cytoskeleton.

Main Idea:

Small proteins are subunits that crisscross the entire cell. Description: Cytoskeleton is a network of PROTEINS that changes to meet the needs of a cell Small proteins are subunits that crisscross the entire cell. Microtubules - Intermediate Filaments- Microfilaments – Gives the cell it shape and acts as “tracks” for the movement of the organelles Gives strength to the cell Smallest tiny threads enable cell to move and divide

Cytoskeleton: A network of protein structures that crisscross the entire cell. Main functions: Maintain the shape of the cell Structure support and strength to the cell Movement of cell Organization and transport of organelles Cell division

3 primary types of cytoskeleton protein fibers Microtubules: cylindrical tubes Give cell its shape Act as “tracks” that organelles move on Form spindle fibers for separating chromosomes (DNA) during cell division (cytokinesis) 2. Intermediate Filaments: Give cell its strength 3. Microfilaments: fine, thread-like fibers Enable cells to move and divide

Function of cytoskeleton: 1. supports and shapes cell 2. provides strength 3. assists in cell division

CYTOPLASM Description: jellylike substance that contains dissolved molecular building blocks (proteins, nucleic acid and mineral ions).

Function: It fills the space between the nucleus and cell membrane. CYTOPLASM Function: It fills the space between the nucleus and cell membrane. Made of a fluid portion called cytosol and water.

Main Idea: Several organelles are involved in making proteins Nucleus: Description: is the stores genetic material (DNA) DNA contains the genes that are the instructions for making proteins

Several organelles are involved in making proteins. Nucleus Nucleolus Endoplasmic Reticulum - rough ER - smooth ER Ribosomes Golgi Apparatus Vesicles

Nucleus Stores and protects the DNA Make the DNA available for use at proper time Contains the nucleolus

The nucleus is enclosed in a double membrane called the nuclear envelope. The nuclear envelope has pores that act as doors between the nucleus and the cytoplasm.

Nucleolus is a dense region inside nucleus  Nucleolus is a dense region inside nucleus. This is an area where ribosomes form, (ribosomes: combination of proteins and RNA molecules) These are essential for creating proteins.

Endoplasmic Reticulum (ER): Network of interconnected, folded membranes that form a maze of enclosed spaces called cisternae. The ER is connected to the nucleus. Function: Protein synthesis Lipid synthesis Detoxification

Endoplasmic Reticulum (ER): Network of interconnected folded membranes. The composition is similar to that of cell membrane and nuclear membrane. In between the wavy maze-like section is a material called lumen.  

Endoplasmic Reticulum Function: 1. Production of proteins and lipids Proteins and lipids are created on the surface of the ER and inside the lumen. 2. ER is a transport system for proteins.

There are two types of endoplasmic reticulum: Rough ER with ribosomes on it Smooth ER without ribosomes Makes lipids and performs a variety of other functions

Ribosomes: They are made of RNA (ribonucleic acid) and protein and are manufactured in the nucleus. Function: link amino acids together to form proteins

Golgi apparatus Consist of closely layered stacks of membranes enclosed spaces Function: Processes, sorts and delivers proteins

Vesicles and Vacuoles are similar in that both are storage organelles. Membrane bound sacs that separate some materials from the rest of the cytoplasm These sacs are short-lived and recycled.

Generally, vacuoles are larger than vesicles Generally, vacuoles are larger than vesicles. Plant cells generally have one large central vacuole that takes up most of the space within the cell and is used for storage of all sorts of molecules.

Vesicles are membrane-bound sacs that hold materials

Vacuoles Function: sac used for the storage of materials- in plant cells usually large

Mitochondria Function: supply energy to the cell by converting molecules from food into usable energy

Mitochondria are found in nearly all eukaryotic cells, usually several or many per cell.

Mitochondria consist of a smooth outer membrane and a convoluted inner membrane separated by an intermembrane space. The convolutions of the inner membrane are called cristae and the space inside the inner membrane is the mitochondrial matrix.

Lysosomes Function: contain enzymes to digest and destroy materials

Lysosomes: Organelles that contain digestive hydrolytic enzymes Lysosomes: Organelles that contain digestive hydrolytic enzymes. Membrane surrounding the lysosome prevents the digestive enzymes from destroying the cell. Function: Intracellular digestion Digest excess or worn out organelles Digest food particles Digest viruses or bacteria Digest dead cells

The purpose of the lysosome is to digest things The purpose of the lysosome is to digest things. They might be used to digest food or break down the cell when it dies.

Centrosomes and Centrioles The centrosome is a small region of cytoplasm that produces microtubules. In animal cells, it contains two small structures called centrioles.

Centrioles Functions: 1. Help divide DNA 2. Form cilia and flagella

Main Idea: Plant cells have cell walls and chloroplasts Plant cells have two features not shared by animal cells: cell walls and chloroplasts.

Cell walls Function: provide rigid support.

Chloroplasts Function : helps a plant convert solar energy to chemical energy. (make food for the plant)

Time to answer the objectives from 3-2 Describe the internal structure of eukaryotic cells. Summarize the functions of organelles in plant and animal cells.

Time to answer the objectives from 3-2 Describe the internal structure of eukaryotic cells. Inside eukaryotic cells there is a cell structure formed from….. the cytoskeleton inside the cell where the organelles rest

Time to answer the objectives from 3-2 2. Summarize the functions of organelles in plant and animal cells. The nucleus, ER, ribosomes, and golgi apparatus work together to….. to make and transport proteins. Mitochondria… supplies energy to the cell.