Cell Structure and Function -...
Transcript of Cell Structure and Function -...
Chapter 4: Cell Structure
• Section 1: “The History of Cell Biology”
• Section 2: “Introduction to Cells”
• Section 3: “Cell Organelles and Features”
• Section 4: “Unique Features of Plant Cells”
Saturday, January 1, 2011
Discovery of Cells• 1665 - Robert Hooke discovered
cells in cork
• 1673 - Leeuwenhoek was the first to view live cells under a ‘scope
• 1838 - Matthias Schleiden discovered cells in all plants
• 1839 - Theodor Schwann discovered cells in all animals
• 1858 - Ruldolph Virchow discovered cells can only come from cells
Saturday, January 1, 2011
Cell Theory
• All living things are made up of one or more cells
• Cells are the basic unit of structure and function in organisms
• All cells arise from existing cells
Saturday, January 1, 2011
Chapter 4: Cell Structure
• Section 1: “The History of Cell Biology”
• Section 2: “Introduction to Cells”
• Section 3: “Cell Organelles and Features”
• Section 4: “Unique Features of Plant Cells”
Saturday, January 1, 2011
Structure and Function• A cell’s shape reflects its function
• cells are limited by surface-area-to-volume ratio
• small surface-area-to-volume ratio helps with:
• exchanging material with surroundings
• less waste/needs less nutrients
Saturday, January 1, 2011
Prokaryotic Cell• no nucleus (Pro = No!),
genetic material is free-floating
• no membrane-bound organelles
• cell membrane: cell’s outer boundary
• ribosome: makes proteins
• cytoplasm: fluid in the cell
• flagella: for movementSaturday, January 1, 2011
Eukaryotic Cell
• DNA inside nucleus
• membrane-bound organelles carry out specific functions in the cell
Saturday, January 1, 2011
Organization• Plants: Cell Leaf Tissue Leaf
• Humans: Cell Lung Tissue Lung Respiratory System
TISSUECELL ORGANORGANSYSTEM
Saturday, January 1, 2011
Organization
• Tissue: distinct group of cells
• Organs: specialized structure with a specific function
• Organ System: group of organs that carry out body functions
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Body Types• colonial organism: cells
connected in a group but do not depend on each other for survival
• multicellular organism: most begin as a single cell; as the organism grows, the cells differentiate into specialized cells
Saturday, January 1, 2011
Chapter 4: Cell Structure
• Section 1: “The History of Cell Biology”
• Section 2: “Introduction to Cells”
• Section 3: “Cell Organelles and Features”
• Section 4: “Unique Features of Plant Cells”
Saturday, January 1, 2011
Cell Diversity
• Different organelles and features allow cells to function in a variety of unique ways
• EX: muscle cells have a lot of mitochondria (for energy)
Saturday, January 1, 2011
Inside the Eukaryotic Cell• cytoskeleton: helps the cell
move, keep its shape, and organize its parts
• nucleus: surrounded by a double membrane called the nuclear envelope; stores genetic information
• ribosomes: make proteins
• Golgi Apparatus: modifies, sorts, and packages proteins for transport
• vesicle: sac formed by a membrane
• lysosome: vesicle with enzymes to break down large molecules
• Smooth ER: no ribosomes; makes lipids and breaks down toxic substances
• Rough ER: ribosomes attached; prepares proteins for transport out of cell
• Mitochondria: uses energy from organic compounds to make ATP; has own DNA
Saturday, January 1, 2011
Cell Membrane• cells maintain homeostasis
by controlling the movement of substances across the cell membrane
• A lipid bilayer forms the cell membrane
• polar head
• non-polar tail
Saturday, January 1, 2011
Chapter 4: Cell Structure
• Section 1: “The History of Cell Biology”
• Section 2: “Introduction to Cells”
• Section 3: “Cell Organelles and Features”
• Section 4: “Unique Features of Plant Cells”
Saturday, January 1, 2011