Cell Structure and Function Cells Smallest living unit

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Cell Structure and Function

Cell Structure and Function

Cells • Smallest living unit • Most are microscopic

Cells • Smallest living unit • Most are microscopic

Discovery of Cells • Robert Hooke (mid-1600 s)

Discovery of Cells • Robert Hooke (mid-1600 s)

Principles of Cell Theory • All living things are made of cells • The

Principles of Cell Theory • All living things are made of cells • The Cell is a basic unit of life • All cells arise from preexisting cells

Cells Have Large Surface Area-to-Volume Ratio

Cells Have Large Surface Area-to-Volume Ratio

Cell Types • Prokaryotic • Eukaryotic

Cell Types • Prokaryotic • Eukaryotic

Prokaryotic Cells • First cell type on earth • Cell type of Bacteria and

Prokaryotic Cells • First cell type on earth • Cell type of Bacteria and Archaea • No membrane bound nucleus

Eukaryotic Cells • Nucleus bound by membrane • Include fungi, protists, plant, and animal

Eukaryotic Cells • Nucleus bound by membrane • Include fungi, protists, plant, and animal cells • Possess many organelles Protozoan

Representative Animal Cell

Representative Animal Cell

Representative Plant Cell

Representative Plant Cell

Animal Cell

Animal Cell

Plant Cell

Plant Cell

Cell Membrane • Structure: – Phospholipid bilayer with proteins and carbohydrates – Thin, flexible

Cell Membrane • Structure: – Phospholipid bilayer with proteins and carbohydrates – Thin, flexible barrier – Selectively Permeable • Functions – Separates cell from surroundings – Regulates molecules into/out of cell (food, water, wastes, etc. ) Found in all cells

Cell Wall • Structure: – Made of cellulose (a carbohydrate) and proteins – Rigid

Cell Wall • Structure: – Made of cellulose (a carbohydrate) and proteins – Rigid wall outside of cell membrane • Function: – Support and protect – Allows water, oxygen, carbon dioxide and other substances to pass through * Found only in plant, fungi, and algae cells, NOT in animals

Cytoplasm • Viscous fluid containing organelles • components of cytoplasm – Fluid = cytosol

Cytoplasm • Viscous fluid containing organelles • components of cytoplasm – Fluid = cytosol – Organelles (not nucleus) – storage substances Found in plant and animal cells

 • Function: Nucleus – Stores DNA (chromatin), hereditary info for cell – Controls

• Function: Nucleus – Stores DNA (chromatin), hereditary info for cell – Controls cell activities • Components: – Nuclear Envelope: bilayer lipid membrane that surrounds nucleus and has pores or holes to allow materials to move in/out of nucleus – Nucleolus: Small dense region that makes ribosomes Found in plant and animal cells

Ribosomes – Most numerous cell part • Structure: – Made of RNA and protein

Ribosomes – Most numerous cell part • Structure: – Made of RNA and protein • Function: – Synthesis of Proteins (make proteins) Found in plant and animal cells

Rough and Smooth Endoplasmic Reticulum • Structure: – Internal membrane system – Stacks of

Rough and Smooth Endoplasmic Reticulum • Structure: – Internal membrane system – Stacks of flattened sacs • Rough: has ribosomes- gives a bumpy appearance • Smooth: no ribosomes- looks smooth

Rough and Smooth Endoplasmic Reticulum (cont. ) • Function: – Intracellular highway—moves molecules around

Rough and Smooth Endoplasmic Reticulum (cont. ) • Function: – Intracellular highway—moves molecules around the cell • Rough: chemically changes proteins made by ribosomes, sends proteins to Golgi for export • Smooth: synthesizes lipids and cell membrane parts, detox Found in plant and animal cells

Golgi Apparatus • Structure: – Stacks of flattened membranes • Function: – Processing, packaging,

Golgi Apparatus • Structure: – Stacks of flattened membranes • Function: – Processing, packaging, and secreting proteins – Attach carbs and lipids to proteins – Send proteins to their final destinations Found in plant and animal cells

Lysosome • Structure: – Small sac which contains hydrolytic enzymes – Not in plants

Lysosome • Structure: – Small sac which contains hydrolytic enzymes – Not in plants • Functions: – Digest proteins, carbs, and lipids, DNA or RNA in cell – Removes debris: digests old organelle or viruses and bacteria

Vacuole • Structure: – Large sac filled with enzymes, water, and wastes – In

Vacuole • Structure: – Large sac filled with enzymes, water, and wastes – In plants: VERY large – takes up most of cell – In animals: small – store extra materials • Function: – Storage • Vesicles: small vacuoles involved in transporting substances within cells

Chloroplast • Structure: – Saclike structure that contains chlorophyll (a green pigment) • Function:

Chloroplast • Structure: – Saclike structure that contains chlorophyll (a green pigment) • Function: – Photosynthesis: Changes sunlight energy to sugar • Found in plants, algae, and some bacteria • NOT found in animals

Mitochondria • Structure: – Has 2 membranes • Function: – “Cellular Respiration: releases energy

Mitochondria • Structure: – Has 2 membranes • Function: – “Cellular Respiration: releases energy from food molecules to power cell (growth, movement, development, etc. ) Found in plant and animal cells

Centrioles • Structure: A pair of small organelles made of microtubuless • Function: Help

Centrioles • Structure: A pair of small organelles made of microtubuless • Function: Help in the formation of the spindle fibers used in cell division Only found in animal cells