Think positive… Essential Question: How do each of the organelles in a cell function?

1/13/12-Get your book. Set out your plant/animal diagrams. Do-Now: Provide the FUNCTION of the following cell parts. Nucleus f. Endoplasmic Reticulum Nucleolus g. Golgi Apparatus Cell membrane h. vacuole Cell wall i. lysosome Mitochondria j. chloroplast

Cell Membrane The entire cell is surrounded by a thin membrane. Function: controls which substances pass into & out of the cell–it’s selectively permeable

(Cell membrane continued) Structure: composed of phospholipids & proteins in a double layer or bilayer

Each phospholipid has a polar “head” & two non-polar “tails” (Cell membrane continued) Each phospholipid has a polar “head” & two non-polar “tails” The head of the phospholipid is hydrophilic & the tails are hydrophobic. Head Tails

Floating around in the cell membrane are different kinds of proteins. (Cell membrane continued) Floating around in the cell membrane are different kinds of proteins. This model is called the fluid mosaic model. The positions of the lipids & proteins is constantly changing.

Organelles: Cytoplasm: lies between the cell membrane & the nucleus & contains the various organelles of the cell. cytoplasm

Endoplasmic reticulum (ER)- functions as intercellular highway for molecules to move from one part of the cell to another Endoplamsic reticulum

There are two types of ER Endoplasmic reticulum continued There are two types of ER a. Rough ER –has ribosomes on it, transports proteins in the cell b. Smooth ER – no ribosomes, produces lipids Rough ER Smooth ER

vesicle budding from rough ER ribosome vesicle (mitochondrion) space inside smooth ER Fig. 4.14, p. 65

Ribosomes –make proteins, attached to the ER or float freely in the cytoplasm

Golgi Apparatus- packages proteins for secretion out of cell

ROUGH ER SMOOTH ER GOLGI BODY vesicle from ER, about to fuse with the Golgi membrane internal space budding vesicle Fig. 4.15, p. 65 0.25 µm

Lysosomes – produced by Golgi; contain strong digestive enzymes;suicide sac

Mitochondria – powerhouses of the cell; produce ATP (energy)

Chloroplasts – found in organisms that carry on photosynthesis

Microfilaments Microtubules Cytoskeleton: a network of long protein strands that gives the cell support & movement. 2 types: Microfilaments Microtubules

Components of the Cytoskeleton Microtubules Help with cell division & movement Microfilaments Help with movement & shape

Cilia & Flagella -hairlike structures, extend from surface of cell, assist in movement

vacuoles- storage of food, enzymes & wastes

The Nucleus- control center Separated from the cytoplasm by nuclear envelope (double membrane) Contains fine strands of chromatin (DNA) which will coil up to form chromosomes Large dark structure –nucleolus(RNA)

1/17/12 Do-Now: Take out your plant/animal cell wkst. How are the cell & nuclear membranes similar? Different? Give the FUNCTION of the following organelles. a. nucleolus b. flagella c. lysosome

Differences in Plant and Animal Cells A Plant Cell An Animal Cell

Differences in Plant and Animal Cells

-cell walls made of cellulose in addition to membranes Plant cells have: -cell walls made of cellulose in addition to membranes Provide structure & support

vacuole Plant cells have: -a large central vacuole which provides turgor pressure vacuole

Plant cells have: Plastids to store food or pigments Leukoplasts – white – store starch Chromoplasts – red, yellow, blue Chloroplasts - green

Animal cells have… centrioles (during cell reproduction) Small vacuoles (if at all) lysosomes

1/18/12-Get your book & take out your homework. Do-Now: 1. If a cell were a city, what organelles would represent the following things? City Hall b. Power Plant c. Waste Management d. UPS 2. If a cell were a factory, what organelles would represent the following things? Main Office b. Doors c. Generator d. Packaging Center

8/31/10-Pick up the book that matches your desk number. Do-Now: Pick up & complete the word search on the shelf. Small Group Review tomorrow before school. See me for a pass. Test TOMORROW GRECHO, Cell Theory, 5 Scientists, Cell Structures & Functions ~55 questions True/False MC Short Answer Fill In