Bio ch 5

Cell theory

1.All living organisms are composed of one or more cells2.Cells are the smallest units of life3.New cells come only from pre-existing cells by cell division

Besides the proteins being processed for distribution, what other components could be expected to be found inside the Golgi apparatus?

Enzymes

Lysosome

Lysosomes•Lysosomes: Contain digestive enzymes that hydrolyze macromolecules (proteins, carbohydrates, nucleic acids, and lipids) into monomers.•Primary lysosomes originate from the Golgi apparatus.•Food molecules enter the cell by phagocytosis—a phagosome is formed.•Phagosomes fuse with primary lysosomes to form secondary lysosomes. Enzymes hydrolyze the food molecules

Eukaryotic cells

Membrane bound nucleus,cells are larger and structurally complex, have membrane bound organelle

Semiautonomous organelle

Mitochondria and chloroplasts

Cytoskeleton

Network of fibers extending throughout the cytoplasm-Cell shape and structure-Cell motility-Anchors organelles-Serves as a transport system

Peroxisomes

Peroxisomes•Peroxisomes: Collect and break down toxic byproducts of metabolism such as H2O2, using the enzyme catalase

How could scientists use radioisotopes to study the function of the Golgi apparatus?

Radiolabeled sugars could be tracked as they are covalently attached to proteins within the Golgi apparatus.

Cytosol

Region of a eukaryotic cell that is outside the cell organelles but inside the plasma membrane

Endoplasmic reticulum

Rough endoplasmic reticulum (rough ER)-Studded with ribosomes-Involved in protein synthesis and sorting, glycosylation.•Smooth endoplasmic reticulum (smooth ER)-Lacks ribosomes-Detoxification, carbohydrate metabolism, calcium balance, synthesis, and modification of lipids, synthesis of phospholipid

Ribosomes•

Sites of polypeptide synthesis

A student discussing the role of the Golgi apparatus in cells makes the following three statements: A variety of proteins enter the Golgi from vesicles that pinch off from the rough ER. Within the Golgi apparatus, different proteins are modified by the activities of sugar molecules. After modification, the proteins move within vesicles to specific locations in the cell. Evaluate the accuracy of the student's statements.

The first and third statements are accurate; the second statement is not accurate.

Golgi apparatus

Vesicles transport materials between stacks•Three overlapping functions-processing, sorting and secretion of protei

The correct order of movement of proteins through the Golgi apparatus is

cis, medial, trans.

Prokaryotic cells

do not have a membrane bound nucleus, tend to be smaller and more structurally simple

Cytoplasm

includes everything inside the plasma membrane -Cytosol, the endomembrane system and the semiautonomous organelles11

endosymbiosis theory

proposes that mitochondria and plastids arose when one cell engulfed another ce

Vacuoles

storage

All of the following molecules can be found in extracellular structures except

tubulin

Microscopy (3 important parameters)

•Magnification-Ratio between the size of an image produced by a microscope and its actual size•Resolution-Ability to observe two adjacent objects as distinct from one another•Contrast-How different one structure looks from another - enhanced by dyes

Endomembrane system

•Network of membranes enclosing the nucleus, endoplasmic reticulum, Golgi apparatus, lysosomes, and vacuoles•Also includes plasma membrane•May be directly connected to each other or pass materials via vesicle