Chapter 3 Cells Prefix cyto-means “cell” Suffix –cyte means “cell” Ex. Erythrocyte- red blood cell cytologist-one who studies cells

Prokaryote vs. Eukaryote Prokaryotes are simple cells without a nucleus and most of the organelles found in eukaryotes. Bacteria are the best examples. Eukaryotes are larger cells with a nucleus and many organelles. Animals, Plants, Protists, and Fungi.

Main parts of the cell Cell Membrane: surrounds contents of the cell; allows substances to enter and leave; selectively-permeable(picks and chooses who comes and goes) phospholipid bilayer

Cytoplasm: jellylike substance that contains most of the organelles; most of the cell activities take place here

Organelles 1-endoplasmic reticulum: “transportation system” of the cell; membrane canals that connect nuclear envelope and the cell membrane. Rough-has ribosomes Smooth-no ribosomes

2-ribosomes: involved in protein synthesis; may be found on the ER or free-floating in cytoplasm. Ribo=Robocop(muscles)

3-Golgi Apparatus: “Appawrapus”. found near nucleus; packaging 3-Golgi Apparatus: “Appawrapus” found near nucleus; packaging center for the cell; membrane canals that form vesicles full of protein/products of the cell.

4-Mitochondria: “mighty mouse”;. produces energy for the cell; 4-Mitochondria: “mighty mouse”; produces energy for the cell; elongated sacs found throughout cell

5-Lysosomes: “lysolsomes”. digestion center of cell; 5-Lysosomes: “lysolsomes” digestion center of cell; cleans up worn out parts of cell or foreign invaders;contain powerful enzymes

6-Centrosome: “traffic cop stays. in the center of the road”; 6-Centrosome: “traffic cop stays in the center of the road”; made of 2 cylinders; helps distribute chromosomes during mitosis

7-vesicle: bubblelike sac made. from either the Golgi 7-vesicle: bubblelike sac made from either the Golgi Apparatus or the cell membrane;contains some liquid or solid that is being transported in the cell.

8-Cilia/Flagella: hairlike projections that extend from cell. Cilia-short, hairlike, found in groups, move things around cell. Flagella-long, whiplike, found by itself, moves the cell itself.

9-Microfilaments/Microtubules:. both are threadlike and are 9-Microfilaments/Microtubules: both are threadlike and are found in cytoplasm Microfilaments-move cell Microtubules-form internal skeleton of cell

Cell Nucleus Control center of cell Usually found in center of cell Contains nucleolus –made of RNA Contains chromatin(protein and DNA…forms chromosomes during mitosis).

Passive movements in cells 1-Diffusion: molecules/ions move from high to low concentration. Ex. O2 picked up by RBC in lungs and dropped off at cells; perfume diffuses from an open bottle.

Passive, cont. 2-Facilitated Diffusion: molecules move through a membrane by a carrier molecule. Ex. Movement of glucose across cell membrane requires insulin

Passive, cont. 3-Osmosis: water molecules move from high to low concentration through a selectively permeable membrane. Ex. Distilled water entering a cell

Passive, cont. 4-Filtration: molecules are “forced” from high pressure to low pressure. Ex. Molecules leaving capillaries

Active methods of transport 1-Active transport: molecules or ions are “carried” through membranes by other molecules from low to high concentration; requires the use of energy. Ex. Movement of ions

Active, cont. 2-Pinocytosis: cell membrane gobbles up a liquid;requires energy 3-Phagocytosis: cell membrane gobbles up a solid;requires energy

PMAT Life Cycle of the cell Mitosis: process by which the body cell divides to create two identical daughter cells. PMAT

Phases of Mitosis 1-Prophase: chromosomes form; centrioles move to opposite ends of cell. “Decorate for the Prom” 2-Metaphase: chromosomes line up in the middle of the cell along spindle fibers. “Meet on dance floor”

3-Anaphase: chromosomes split sending each part toward the centrosomes 3-Anaphase: chromosomes split sending each part toward the centrosomes. “Ana gets mad and walks away from her date”

4-Telophase: final stage; nuclear membrane pinches in making 2 nuclei-not 2 complete cells yet “Ana telophones her date to make the final break”

Cytokinesis: not a phase of mitosis, but the division of the cell membrane and cytoplasm. Interphase: the in between phase; the cell is carrying on its normal activities, including growth and replication

Cell Differentiation Process by which cells develop differently to do different jobs. Ex. RBCs carry O2, nerve cells send messages, etc. Unsure of mechanism; some of the information carried in the DNA is “switched on” in some cells and not in others.

Cancer Changes in the cells of the body that can occur in any tissue. Cancer cells take oxygen and nutrients away from healthy cells and tumors impair normal organ function.

Effects of cancer on cells 1-hyperplasia: the cells divide and produce large #s of cells. 2-anaplasia: abnormal cell structure that causes the cell to function improperly. 3-metastasis: cancer cells move from where they originate to other organs.