Lesson 4 - The Cell 1

A set of vocabulary flashcards based on cell structure, microscopy, and organelles listed in the lecture terms.

Light microscope

An optical instrument with lenses that refract visible light to magnify images of specimens.

Scanning electron microscope

A microscope that uses an electron beam to scan the surface of a sample, usually coated with a thin film of gold, to produce a 3D image of its topography.

Transmission electron microscope

A microscope that passes an electron beam through a very thin section of a specimen to study internal cellular ultrastructure.

Electron microscope

A microscope that uses magnets to focus an electron beam on or through a specimen, achieving much higher resolution than a light microscope.

Cytosol

The semifluid, jelly-like portion of the cytoplasm in which subcellular components are suspended.

Nucleoid

A non-membrane-enclosed region in a prokaryotic cell where its genetic material (DNA) is concentrated.

Nucleus

The membrane-enclosed organelle of a eukaryotic cell that contains the genetic material in the form of chromosomes.

Chromosomes

Cellular structures consisting of one DNA molecule and associated protein molecules, carrying genetic information.

Glycoproteins

Proteins that have carbohydrates covalently attached to them.

Ribosomes

Cellular complexes made of ribosomal RNA and protein that carry out protein synthesis.

Endoplasmic reticulum

An extensive membranous network in eukaryotic cells, continuous with the outer nuclear membrane, consisting of rough and smooth regions.

Phagocytosis

A type of endocytosis in which large particulate substances or small organisms are engulfed by a cell.

Eukaryotic Cell

A type of cell with a membrane-enclosed nucleus and membrane-enclosed organelles.

Cytoplasm

The contents of the cell bounded by the plasma membrane, excluding the nucleus in eukaryotic cells.

Nuclear envelope

The double membrane that surrounds the nucleus, perforated with pores that regulate traffic with the cytoplasm.

Chromatin

The complex of DNA and proteins that makes up eukaryotic chromosomes.

Endomembrane system

The collection of membranes inside and surrounding a eukaryotic cell, related through direct physical contact or by transfer via membranous vesicles.

Smooth ER

The portion of the endoplasmic reticulum that is free of ribosomes, involved in lipid synthesis, carbohydrate metabolism, and detoxification.

Golgi apparatus

An organelle in eukaryotic cells consisting of stacks of flat membranous sacs that modify, store, and ship products of the endoplasmic reticulum.

Vacuole

A membrane-bounded vesicle whose function varies in different cell types, including storage, waste disposal, and water balance.

Organelle

Any of several specialized membrane-enclosed structures suspended in the cytosol of eukaryotic cells.

Cell fractionation

The disruption of a cell and separation of its major organelles and components by centrifugation at successively higher speeds.

Prokaryotic Cell

A type of cell lacking a membrane-enclosed nucleus and membrane-enclosed organelles.

Plasma membrane

The membrane at the boundary of every cell that acts as a selective barrier, regulating the passage of substances into and out of the cell.

Nuclear lamina

A netlike array of protein filaments lining the inner surface of the nuclear envelope that helps maintain the shape of the nucleus.

Nucleolus

A specialized structure in the nucleus consisting of chromosomal regions and ribosomal RNA, responsible for synthesizing ribosomal subunits.

Vesicles

Small membranous sacs in the cytoplasm that store or transport materials within the cell.

Rough ER

The portion of the endoplasmic reticulum studded with ribosomes, involved in synthesizing membrane proteins and secretory proteins.

Lysosome

A membrane-enclosed sac of hydrolytic enzymes found in animal cells used to digest macromolecules and damaged organelles.