September 11, 2018 LT: I can identify cell organelles. Warm-Up What are the different shapes of bacteria? What is the purpose of cells having a cell membrane and cell wall?

Introduction to Cells

Cells First discovered by Robert Hooke in 1665 Looked at pieces of cork under a microscope and said they looked like a monks cell 1839: Theodor Schwann determined all living things are made of cells Drawing made by Robert Hooke when he first saw cells

Cell Theory All organisms are made of cells. All existing cells are produced by other living cells. The cell is the most basic unit of life.

Two Categories of Cells Prokaryote: NO nucleus Contains a cell membrane, cytoplasm and ribosomes All unicellular Kingdoms bacteria and archaea Eukaryote: nucleus Contains: cell membrane, cytoplasm and membrane bound organelles Multicellular or unicellular Kingdoms protista, fungi, plant and animal

Cell Organelles

Cytoskeleton Supports and shapes cell Aids in cell mobility

Cell Membrane Protects cell Regulates what enters and leaves the cell

Nucleus Stores DNA Contains instructions for making proteins Controls cell processes

Nucleolus Synthesizes ribosomes that are sent to the rough endoplasmic reticulum

Nuclear Membrane and Nuclear Pores Nuclear membrane surrounds nucleus Nuclear pores allow substances to pass through nucleus into cytoplasm

Cytoplasm Jellylike substance that contains organelles and dissolved materials such as proteins, minerals and sugars

Centrioles Help divide cells during cell division Only in animal cells

Mitochondria Makes energy for the cell in the form of ATP “powerhouse” of the cell

Ribosomes Synthesize proteins

Endoplasmic Reticulum Pathway for molecules to move from one part of the cell to the other Rough ER: prepares proteins for export, has ribosomes Smooth ER: synthesizes fats and breaks down toxins (such as drugs and alcohol)

Rough and Smooth ER

Golgi Apparatus Processes and packages substances produced by the cell Modifies proteins

Lysosome Digests molecules, old organelles and foreign substances Gets rid of waste products

Peroxisomes Protects cell from its own production of hydrogen peroxide Enzymes break down hydrogen peroxide to H20 and O2

Cilia and Flagella Aid in cell movement

Cell Wall Supports and protects the cell Composed of cellulose (a sugar) Plant, fungi and bacterial cells

Vacuole Stores materials needed by the cell such as water and food molecules All plant cells (very large, called central vacuole) In animal cells very small (not in most)

Chloroplast Carries out photosynthesis Supplies chlorophyll Plant cells and some protists