Chapter 6 vocab Flashcards
Cell wall
A PROTECTIVE LAYER EXTERNAL TO THE PLASMA MEMBRANE in the cells of plants, prokaryotes, fungi, and some protists. Polysaccharide such a cellulose (in plants and some protists), chitin (in fungi), and peptidoglycan (in bacteria) are an important structural component of cell walls
Central vacuole
A membranous sack in a mature plant cell with diverse roles in reproduction growth and development
Chloroplasts
A green pigment located within the chloroplasts of plants and algae, and in the membranes of certain prokaryotes. Chlorophyll a participate directly in the light reactions which convert solar energy to chemical energy.
Chromosomes
A STRUCTURE CARRYING GENETIC MATERIAL, found in the nucleus of eukaryotic cells. Each chromosome consists of one very long DNA molecule and associated proteins. ( A bacterial chromosome usually consist of a single cellular DNA molecules and associated proteins. It is found in the nucleoid region which is not membrane-bound)
Chromatin
The complex of DNA and proteins that makes up a eukaryotic chromosome. When the cell is not dividing, chromatin exists in its dispersed form, a massive very long, thin fibers that are not visible with a light microscope.
Cilia
A short cellular appendage containing microtubules. A motile cilium is specialized for locomotion and is formed from a core of nine outer doublet microtubules and two inner single microtubules ensheathed in an extension of plasma membrane. A primary cilium is usually non-motile and plays a sensory and signaling roll; it lacks the two inner microtubules
Cytoplasm
The contents of the cell, exclusive of the nucleus and bounded by the plasma membrane
Cytoskeleton
A network of microtubules, microfilaments, and intermediate filaments that branch throughout the cytoplasm and serve a variety of mechanical, transport, and signaling functions
Electron microscope
A microscope that uses magnets to focus an electron beam on or through a specimen, resulting in resolving power a thousandfold greater than that of a light microscope. A transmission electron microscope (TEM) is used to study the internal structure of thin sections of cells. A scanning electron microscope (SEM) is used to study the fine details of cell surfaces
Cytosol
The semi fluid portion of the cytoplasm
Flagella
A long cellular appendage specialized for locomotion. The flagella of prokaryotes and eukaryotes differ in both structure and function. Like motile cilia, eukaryotic flagella have a core with nine outer doublet microtubules and two inner single microtubules ensheathed in an extension of the plasma membrane
Eukaryotic cell
A type of cell with a membrane enclosed nucleus and membrane enclosed organelles. Organisms with eukaryotic cells(protists plants fungi and animals) are called eukaryotes
Light microscope
And optical instrument with lenses that refract (bend) visible light to magnify images of specimens
Golgi apparatus
An organelle in eukaryotic cells consisting of stacks of flat membranous sacs that modify, store, and route products of the endoplasmic reticulum and synthesize some products, notably non cellulose carbohydrates
Lysosome
A membrane enclosed stack of hydrolytic enzymes found in the cytoplasm of animal cells and some protists
Mitochondria
An organelle in eukaryotic cells that serves as the site of cellular respiration
Organelles
Any of several membrane enclosed structures with specialized functions, suspended in the cytosol of eukaryotic cells
Nuclear envelope
The double membrane in a eukaryotic cell that encloses the nucleus, separating it from the cytoplasm
Nuclear lamina
A net like a ray of protein filaments letting the inner surface of the nuclear envelope; it helps maintain the shape of the nucleus
Nucleus
An atom’s central core, containing protons and neutrons
The chromosome containing organelle of a eukaryotic cell
A cluster of neurons
Nucleolus
A specialized structure in the nucleus, consisting of chromatin regions containing ribosomal RNA genes along with ribosomal proteins imported from the cytoplasmic site of rRNA synthesis and ribosomal subunit assembly
Prokaryotic cell
A type of cell lacking a membrane enclosed nucleus and membrane enclosed organelles. Organisms with prokaryotic cells(bacteria and archaea) are called prokaryotes
Plasma membrane
The membrane at the boundary of every cell that acts as a selective barrier, regulating the cells chemical composition
Peroxisome
An organelle containing enzymes that transfer hydrogen (H2) from various substrates to oxygen (O2) producing and then degrading hydrogen peroxide (H2O2)
Ribosomes
A complex of rRNA and protein molecules that functions as a site of protein synthesis in the cytoplasm; consists of a large and a small subunit. In eukaryotic cells, each subunit is assembled in the nucleolus
Smooth ER
That portion of the endoplasmic reticulum that is free of ribosomes
Rough ER
That portion of the endoplasmic reticulum studded with ribosomes
Thylakoids
A flattened membranous sac inside a chloroplast. Thylakoids occur in an interconnected system in the chloroplast and contain the molecular machinery used to convert light energy to chemical energy
Stroma
Within the chloroplast, the dense fluid of the chloroplast surrounding the thylakoids membrane; involved in the synthesis of organic molecules from carbon dioxide and water
Transport vesicles
A tiny membranous sack in a cells cytoplasm carrying molecules produced by the cells
