Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
26 Cards in this Set
- Front
- Back
Plasma Membrane
|
Separates the cell from its surrounding environment.
|
|
Cytoplasm
|
Thick gel-like substance inside of the cell composed of numerous organelles suspended in watery cytosol.
|
|
Nucleus
|
Large membranous structure near the center of the cell.
|
|
Membranous Organelles
|
Sacs and canals made of the same material as the plasma membrane.
|
|
Fluid Mosaic Model
|
Theory explaining how cell membranes are constructed.
|
|
Cell Membranes
|
Double layer of phospholipid molecules - Heads are hyrophilic, tails are hydrophobic. Most of the bilayer is hydrophobic.
|
|
Transport Proteins
|
Proteins embedded in the phospholipid bilayer that serve as passages for Na+ ions or glucose.
|
|
Nonmembraneous Organelles
|
Made up of microscopic filaments or other nonmembraneous materials.
|
|
Rough Endoplasmic Reticulum
|
Ribosomes synthesize proteins , which move toward the golgi apparatus and then eventually leave the cell.
|
|
Smooth Endoplasmic Reticulum
|
Synthesize certain lipids and carbohydrates and creates membranes for use throughout the cell.
*Removes and stores Ca++ from cells interior. |
|
Ribosomes
|
*Each one is a nonmembranous structure made of two pieces, a large subunit and and a small subunit. Each unit is composed of rRNA.
*Free ribosomes make proteins for the cells domestic use. |
|
Golgi Apparatus
|
Membranous organelle consisting of cisternae stacked on one another and located near the nucleus.
*Processes protein molecules from the E.R. *Processed proteins leave the final cisternae in a vesicle; contents may then be excreted from the cell. |
|
Lysosomes
|
The digestive system of the cell.
*Made of microscopic membranous sacs that have "pinched off" from the golgi apparatus. |
|
Proteasomes
|
Hollow protein cylinders found throughout the cytoplasm.
*Breakdown abnormal/misfolded proteins and normal proteins no longer needed by the cell. |
|
Peroxisomes
|
Small membranous sacs containing enzymes that detoxify harmful substances that enter the cells (often seen in kidney and liver cells)
|
|
Mitochondria
|
The power plant of the cell. Enzymes catalyze series of oxidation reactions that provide 95% of the cells energy.
*Each mitochondrion has a DNA molecule, allowing it to produce its own enzymes and replicate copies of itself. |
|
Nucleus
|
Spherical body in center if the cell; enclosed by an envelope with many pores.
|
|
Nucleus Structure
|
Nuclear envelope: Composed of 2 membranes each with essentially the same molecular structure as the plasma membrane, surrounding nucleoplasm.
*Contains DNA which appear as the following... - Chromatin threads or granules in non-divinding cells. - Chromosomes in early stages of cell division |
|
Cytoskeleton
|
The cells internal supportin framework made up of rigid, rodlike pieces that provide support and allow movement and mechanisms that can move the cell or its parts.
|
|
Cell Fibers
|
Intricately arranged fibers of varying lengths that form a three-dimensional, irregularly shaped network. Fibers support the ER, mitochondria, and free ribosomes.
|
|
Types of Cell Fibers
|
*Microfilaments - Cellular muscles that are made of thin, twisted strands of protein molecules that lie parallel to the long axis of the cell.
*Intermediate Filaments - Twisted protein strands slightly thicker than microfilaments; they form much of the supporting framework in many types of cells. *Microtubules - Tiny hollow tubes that are the thickest of the cell fibers. They are made of protein subunits arranged in a spiral fashion. Their function is to move things around the cell. |
|
Centrosome
|
An area of the cytoplasm near the nucleus that coordinates the building and breaking of microtubules in the cell.
|
|
Cell Extentions
|
Cytoskeleton forms projections that extend the plasma membrane outward to form tiny, fingerlike processes.
|
|
Types of Cell Extention
|
*Microvilli - Found in epithelial cells that line the intestines and other areas where absorption is important; they help to increase the surface area manyfold.
*Cilia & Flagella - Cell processes that have cylinders made of microtubules at their core; cilia are shorter and more numerous than flagella - flagella are found ONLY in human sperm cells. |
|
Desmosomes
|
Fibers on the outer surface of each desmosome interlock with eachother; anchored internally by intermediate filaments of the cytoskeleton.
|
|
Types of Desmosomes
|
*Spot Desmosomes - Like "Spot Welds" at various points.
*Belt Desmosomes - Encircle the entire cell like a collar. *Gap Junctions - Form channels that join the cytoplasm of two cells - fuse two plasma membranes into a single structure. *Tight Junction - Molecules cannot permeate the cracks of tight junctions; occur in the linig of the intestines and other places where it is important to control what gets through the sheet of cells. |