Topic 2 Cell Types and Cell Structures Living

Topic 2 Cell Types and Cell Structures

Living things are made of…. Cells!!!

Obj 6 Bacterial Cells (unicellular) Prokarote

An amoeba (unicellular) Eukaryote Obj 7

Plants (multicellular) Eukaryotic Obj 7

Animals (multicellular) Eukaryotic Obj 7

The Cell Theory OBJ 4 § Two BIG ideas § All living things are composed of cells § All cells come from other cells § Other parts of Cell Theory § Cells are the fundamental unit of structure and function in all living thing § Activity of the organism depends on the total activity of the independent cells § Energy flow occurs within cells § All cells have the same biochemical composition (made of protein, carbohydrates, lipids and nucleic acids)

OBJ 6, 7 What structures do all cells have in common? § All cells contain nucleic acids (DNA, RNA) § All cells have ribosomes and make proteins § All cells have a cell membrane

HOW DO PROKARYOTIC AND EUKARYOTIC CELLS COMPARE?

Obj 8 PROKARYOTIC (bacterial) CELL EUKARYOTIC CELL

Obj 6, 7 Two Basic Cell Types Organelles No organelles

How do Prokaryotes and Eukaryotes differ? Prokaryotes Structurally simpler Nucleoid - Coiled DNA, free in cytoplasm Size 1 t 0 10 micrometers Bacteria and Archaea Most have a cell wall OBJ 8 Eukaryotes Membrane bound organelles Nucleus (contains DNA) Size 10 to 100 micrometers Protists, Fungi, Plants, Animals Plants have a cell wall

OBJ 8 Plant cells vs. Animal cells Plant cells Cell wall Chloroplasts and Mitochondria Large water vacuole Animal cells Cell Membrane only Mitochondria only

Cell Organelles

Organelle Functional groups 1. Manufacturing 1. Nucleus 2. Ribosomes 3. ER (Rough & Smooth) 4. Golgi apparatus 2. Breakdown/storage 1. Lysosomes 2. Vacuoles 3. Energy Processing 1. Mitochondria 2. Chloroplasts 4. Support, Movement, Communication 1. Cytoskeleton (includes cilia & flagella) 2. Cell membrane 3. Cell Wall

Cell Membrane Obj 6, 7 § Barrier between the outside and inside of a cell § Consists of…. § § Phospholipids Transport proteins Cholesterols (fluidity) Carbohydrates (cell surface markers)

Obj 6, 7 Cytoplasm • Gel like substance that is inside the cell membrane. • Organelles are imbedded in it • Contains dissolved substances • Location of many biochemical reactions

Ribosome Obj 6, 7 • Not membrane bound • Made up of protein and RNA • Involved in Protein Synthesis • Can be free in the cytoplasm or attached to the Endoplasmic Reticulum TEM images of ribosome’s

Obj 7 Nucleus • Location of most of the cells DNA • DNA in chromatin form (DNA wound around special proteins) • Nuclear envelope double membrane with pores TEM image of a plant cell

Obj 7 Nucleolus • Makes ribosomal RNA - important ingredient in protein synthesis

Obj 7 Mitochondrion • Singular form for mitochondria

Obj 7 Mitochondria • Double membrane structure that is the site of aerobic respiration - energy conversion process • Membrane contains many transport proteins that are used in aerobic respiration • Sometimes called the “power house” of the cell TEM image of a Mitochondria

Endoplasmic Reticulum (ER) Obj 7 Rough ER • Part of the internal membrane system (endomembrane system) • Provides division of space with in the cell • Rough ER has attached ribosome’s • Location of protein synthesis • Forms vesicles that deliver “products” to the Golgi apparatus

Obj 7 Smooth Endoplasmic Reticulum

Obj 7 Endoplasmic Reticulum

Obj 7 Golgi Apparatus • Part of the internal membrane system • Forms vesicles for exocytosis • Releases “products” to the external environment • Also forms lysosomes

Obj 7 ER and Golgi Apparatus

Obj 7 Lysosomes • Membrane bound • Contains enzymes • Formed by the golgi apparatus • Fuse with vesicles formed by endocytosis - enzymes digest (intercellular digestion) • Breakdown damaged cell structures

Dynamic Cell: Organelles work together!Rough ER, Golgi Apparatus, lysosomes, food vacuoles and cell membrane

Chloroplasts Obj 7 • Found in plant cells • Location of Photosynthesis

Obj 7 Chloroplasts Light microscope image

Vacuole Obj 7 • Water storage in plant and animal cells • Plant cells have a large central water vacuole • Food vacuoles exist in many organisms

Cell Wall Obj 6, 7 • Rigid structure found in plants and most prokaryotes • Gives plants structure • Matrix of polysaccharides (cellulose) and proteins

Obj 6, 7 Cell Wall

Obj 6, 7 Cytoskeleton • Provides structure and shape to the inside of cells • Organizes and anchors some organelles

Obj 6, 7 Cytoskeleton

Obj 6, 7 Flagella E. coli • Bundled microtubules • Surrounded by the plasma membrane

Obj 6, 7 Cilia • Microtubules • Rhythmic motion produces movement

Centrioles Obj 7 • Structure involved in forming microtubules • Involved in cell replication

Organelle Functional groups 1. Manufacturing 1. Nucleus 2. Ribosomes 3. ER (Rough & Smooth) 4. Golgi apparatus 2. Breakdown/storage 1. Lysosomes 2. Vacuoles 3. Energy Processing 1. Mitochondria 2. Chloroplasts 4. Support, Movement, Communication 1. Cytoskeleton (includes cilia & flagella) 2. Cell membrane 3. Cell Wall

The Dynamic Cell

OBJ 5 Why must cells be small? § Enough materials and internal structures § Surface area to volume ratio

OBJ 5 Surface Area to Volume Ratio