Module 4 Flashcards
The Cell theory states what 3 things?
All living organisms are composed of cells. They may be unicellular or multicellular.
The cell is the basic unit of structure and function in living organisms.
Cells arise from existing cells.
Cytology
The study of cells
Ingestion
The ability to take in nutrients; this includes absorption, which is the ability to bring dissolved materials into the cell
Digestion
The ability to break food or nutrients down into simpler forms (by hydrolysis or with the help of enzymes) so it can be utilized
Respiration
The ability to release energy from the breakdown of food molecules
Transport
The ability to distribute or circulate molecules from one part of a cell to another
Homeostasis
The ability to maintain internal stability (also known as regulation)
Synthesis
The ability to combine simple compounds into complex molecules (same as biosynthesis discussed in Module 2)
Secretion
The ability to release biosynthesized substances
Excretion
The ability to remove soluble metabolic waste from the cell
Egestion
The ability to remove nonsoluble, undigested waste from the cell
Irritability
The ability to respond to stimuli
Movement
The ability to move
Reproduction
The ability to produce more cells
Organelle
A tiny cellular structure that carries out a specific function necessary for the cell to survive
Prokaryotic cell
A cell that has no nucleus or other distinct, membrane-bound organelles
Eukaryotic cell
A cell with a membrane-bound nucleus and other distinct, membrane-bound organelles
Plasma membrane
The semipermeable membrane between the cell contents and the cell’s surroundings
Cytoplasm
A jellylike fluid inside the cell in which the organelles are suspended
Cytoplasmic streaming
The motion of cytoplasm in a cell that results in a coordinated movement of the cell’s content
Ribosomes
Non-membrane-bound organelles responsible for protein synthesis
Middle lamella
The thin film between the cell walls of adjacent plant cells
Nuclear membrane
A highly porous membrane that separates the nucleus from the cytoplasm
Chromatin
Long strands of clusters of DNA and proteins (or RNA and proteins) in the nucleus of a cell
Endoplasmic reticulum
An organelle composed of an extensive network of folded membranes that performs several tasks within a cell
Rough ER
ER that is dotted with ribosomes
Smooth ER
ER that has no ribosomes
Golgi apparatus
The organelles where proteins and lipic are stored and then modified to suit the needs of the cell
Vacuole
Larger membrane-bound organelle used for storage of food, water, or waste
Vesicle
Smaller membrane-bound organelle used mainly for transport of food, waste, or products synthesized for secretion
Secretory vesicle
Vesicle that holds products of biosynthesis (like proteins) and transports them to the plasma membrane for secretion
Central vacuole
A large vacuole that rests at the center of most plant cells and is filled water
Lysosome
The organelle in animal cells responsible for hydrolysis reactions that break down proteins, carbohydrates (polysaccharides, disaccharides), and some lipids
Peroxisome
A cell organelle containing enzymes that catalyze the decomposition of fatty acids and hydrogen peroxide
Mitochondria
Double-membrane-bound organelles in which nutrients are converted to energy
Plastids
Double-membrane-bound organelles found in the cells of plants, algae, and some protozoa, generally involved in either the manufacture or storage of food
Chloroplasts
Plastids containing the green pigment, chlorophyll, used in photosynthesis
Chromoplasts
Plastids containing yellow, orange, or red pigments used in photosynthesis
Leucoplasts
Nonpigmented plastids that store starches or oils
Cytoskeleton
A network of fibers that holds the cell together, helps the cell to keep its shape, and aids in movement
Microfilaments
Fine, threadlike proteins found in the cell’s cytoskeleton
Intermediate filaments
Threadlike proteins in the cell’s cytoskeleton that are roughly twice as thick as microfilaments
Microtubules
Spiral strands of protein molecules that form a tubelike structure
Centrioles
Paired organelles (positioned at right angles to each other) that organize fibers required for cell division; found in animal cells
Centrosome
A small region near the nucleus that is the main organizing site for microtubules; in animal cells it contains the two centrioles
Semipermeable membrane
A membrane that allows some molecules to pass through but does not allow other molecules to pass through
Passive transport
Movement of molecules through the plasma membrane without the need for energy input
Active transport
Movement of molecules through the plasma membrane aided by a process that requires energy input
Concentration
A measurement of how much solute exists within a certain volume of solvent
Concentration gradient
The difference in the concentration of like molecules in two areas, like on each side of a plasma membrane
Diffusion
The random motion of molecules from an area of high concentration to an area of low concentration (with a concentration gradient) until its concentration becomes equal throughout the area (reaches equilibrium)
Osmosis
The diffusion of water through a semipermeable membrane from an area of high water concentration (low solute concentration)
Hypotonic solution
A solution that has a low solute concentration (and so a high water concentration) relative to another solution
Hypertonic solution
A solution that has a high solute concentration (and so a low water concentration) relative to another solution
Isotonic solution
A solution that has the same solute concentration (and water concentration) relative to another solution
Plasmolysis
Collapse of a walled cell’s cytoplasm due to a lack of water
Cytolysis
The rupturing of a cell due to excess internal pressure
Facilitated diffusion
The movement of certain molecules across a cell membrane through protein channels from high concentration to low concentration
Endocytosis
The process of moving particles into the cell by means of vesicles forming from the cell membrane
Exocytosis
The process of moving particles out of the cell by means of vesicle membranes fusing with the cell membrane
Phagocytosis
The endocytic process by which a cell engulfs large, solid particles or cells
Pinocytosis
The endocytic process by which a cell absorbs extracellular fluid containing dissolved particles
