WEEH 2 Notes-Cell Structure and Plasma Membrane ppt

Week Two Cell Structure and Plasma Membrane History of Cells- ’s Anton Von Leeuwenhoek- developed first types of microscopes allowed observation Robert Hooke- named “cells” The Cell Theory: 1. All living things are composed of cells 2. Cells are the basic unit of structure and function in all living things 3. All cells come from pre-existing cells Clever and Quick You Tube about Cell History https:// Cell Types • Prokaryotic Cell- simplest type of cell • No nucleus or membrane bound organelles • Ex: Bacteria • Eukaryotic Cell- most complex • Contains many membrane bound organelles like the nucleus • Ex: Animals, plants, fungi and protists Prokaryotic Cell Diagram Cell Structures and their Function • Cell (Plasma) Membrane: controls what goes in/out of cell • Selectively permeable- lets some things in but not others • Cell Wall: extra layer of protection found in all cells except animal cells. • consists of cellulose and proteins • Nucleus: contains the chromosomes • Nuclear Envelope: membrane with pores that controls what goes in/out of nucleus • Nucleolus: small structure w/in the nucleus contains RNA – site of ribosome production Animal and Plant Cells Cell Structures and their Function cont… • Chromatin/Chromosomes- DNA strands wrapped around a protein core- contains the genes • Cytoplasm: a thick liquid material that contains organelles – always moving(streaming) • Mitochondria: “powerhouse of the cell” • Place where energy from food is stored ATP from cellular respiration • Contains folds called Cristae to increase reaction efficiency • Chloroplasts and Plastids: stores plant pigments like chlorophyll needed for photosynthesis Mitochondria Chloroplasts Cell Structures and their Function cont… • Ribosomes: tiny “dots” that are the site of protein synthesis- free floating or attached to ER • Endoplasmic Reticulum: “ER” – complex network of tubes that connect the cell membrane with the nucleus • Transports materials throughout the cell like a highway • Two Types: • Rough ER- walls covered in ribosomes • Smooth ER- walls are smooth • Golgi Apparatus(Bodies): modifies, packages and distributes the proteins made in ribosomes Endoplasmic Reticulum Golgi Apparatus Protein Pathway Cell Structures and their Function cont… • Lysosomes: “ clean-up crew- garbage collector” • Structures that contain digesting enzymes and chemicals that capture and get rid of foreign materials, old organelles etc. • Also are “Suicide Sacs”- they will release enzymes when cell dies • Vacuoles and Vesicles: specific storage and delivery pouches for water, food, waste and proteins • Cytoskeleton: variety of fibers that support and control movement of and w/in cell • Microtubules: large tube-like structures form cilia and flagella as well as Spindle fibers (Impt mitosis) • Microfilaments: tiny fibers that move cytoplasm cause cytoplasmic streaming(moving organelles around cell) Lysosomes Cytoskeleton Plant vs. Animal Cells Plant vs. Animal Cells Plant Cells • Cell wall • Chloroplasts • Large Central water vacuole • Rectangular rigid shape • No centrioles Animal Cells • No Cell Wall • No Chloroplasts • Smaller water vacuoles • Irregular flexible shape • Centrioles Centrioles Click on this link to watch a good review of Cell Structure Review Cell or Plasma Membrane • Phospholipid Bilayer with imbedded proteins ....................................................CONTINUED,,...................................................