Chapter 2: Cell Flashcards
Cells
Are the basic structural and functional unit of multicellular organisms
Cytoplasm
Contains organelles, fibers (cytoskeleton), and inclusions (carbohydrates, lipids, pigments)
Cytosol
Is a fluid component (gel-like) that contains enzymes, electrolytes, sugars, amino acids, gases, etc.; surrounds the nucleus and organelles
Embryoblast
Aka Inner cell mass - a structure in the early development of an embryo
Blastomere
Produced by cell division (cleavage) of the zygote after fertilization
Plasma membrane (plasmalemma)
Is made of phospholipids, cholesterol, proteins, and oligosaccharides covalently linked to phospholipids or proteins
Phospholipid
Contains a polar hydrophilic head group and two nonpolar hydrophobic fatty acid chains
7.5-10 nm
Plasma membrane width is between __-__ nm; not visible in the LM
Plasma membrane
Has a trilaminar structure and is amphipathic
Integral protein
A protein that is embedded deep within the plasma membrane
Peripheral protein
A protein that is shallow or attached outside of the plasma membrane
Heterogenicity
When membranes differ in their protein make up
Integral proteins
Globular proteins with hydrophilic/hydrophobic regions (one pass or multi pass transmembrane proteins)
Glycolipids and Glycoproteins
Part of cell recognition, cell adhesion, carbohydrate regions/moieties (external surface only); the glycocalyx
Roles of membrane proteins
Pumps i.e. ion channels (active transport); channel proteins (entry/exit); receptors (recognition and binding); transducers; structural (cell to cell junctions)
Membrane proteins
Are synthesized in the RER and modified and completed in the Golgi apparatus
Glycosylation
The process by which a carbohydrate is covalently attached to a target macromolecule, typically proteins and lipid; occurs in the golgi
Phagocytosis
the ingestion of particles such as bacteria or dead cell remnants; macrophages and neutrophils are blood-derives cells that specialize in this
Pinocytosis
cell drinking; involves smaller invaginations of cell membrane which fuse and entrap extracellular fluid and its dissolved contents
Receptor-mediated endocytosis
plasma membrane receptors first bind specific substances; receptor and bound substance then taken up by cell
Clathrin
electron-dense coating on the cytoplasmic surface, contains an abundance of the protein ________
Cilia
short, numerous membrane extensions supported by microtubules
Cilia
move substances over the cell surface
Flagellum
long, singular membrane extension supported by microtubules
Flagellum
propels sperm
Microvilli
numerous thin membrane folds projecting from the free cell surface
Microvilli
increase membrane surface area for greater absorption
Nucleolus
functions in synthesis of ribosomes
Rough endoplasmic reticulum
extensive interconnected membrane network; ribosomes attached on cytoplasmic surface
RER
modifies, transports, and store proteins produced by attached ribosomes; these proteins are secreted, become components of the plasma membrane or serve as enzymes of lysosomes
SER
synthesizes, transports, and store lipids; metabolizes carbohydrates; detoxifies drugs, alcohol, and poisons; forms vesicles and peroxisomes
Smooth endoplasmic reticulum
extensive interconnected membrane network lacking ribosomes
Golgi apparatus
series of several elongated, flattened saclike membranous structures
Golgi apparatus
modifies, packages, and sorts materials that arrive from the ER in transport vesicles; forms secretory vesicles and lysosomes
Vesicles
transport cellular material
Lysosomes
spherical-shaped membrane-bound organelles formed from the golgi apparatus; contains digestive enzymes
Lysosomes
digest microbes or cellular materials
Peroxisomes
smaller, spherical-shaped membrane-bound organelles formed from the ER or through fission; contain oxidative enzymes
Peroxisomes
detoxify specific harmful substances either produced by the cell or taken into the cell; use 02 to remove H+
Cytoskeleton
organized network of protein filaments and hollow tubules, including microfilaments, intermediate filaments, and microtubules
Cytoskeleton
maintains intracellular structural support and organization of cells; participates in cell division; facilitates movement
Microfilaments
actin protein monomers organized into two thin, intertwined protein filaments(actin filaments)
Microfilaments
maintain cell shape; support microvilli; participate in muscle contraction; separate two cells during cytokinesis
Intermediate filaments
provide structural support; stabilize junctions between cells
Microtubules
hollow cylinders composed of tubulin proteins; contains 13 units
Microtubules
maintain cell shape and rigidity; support cilia and flagella; organize and move organelles
Centrosome
organizes microtubules(centrioles); participates in mitotic spindle formation during cell division
Proteasomes
degrade and digest damaged or unneeded proteins; ensure quality of exported proteins
Intermediate filaments
keratins, vimentin, neurofilaments, and lamins are all ______
Keratins
major component of epithelial cells; strength and abrasion resistance;
Vimentin
found in most cells derived from embryonic mesenchyme; most common IF proteins
Desmin
structural components of the sarcomeres (basic contractile nit of muscle fiber)
Neurofilaments
IF of neurons
Lamins
Intermediate filaments of the nucleus
Cell inclusions
not organelles and have very little metabolic activity; serve as temporary storage for cellular moelcules
Cell inclusions
lipid droplets and glycogen granules are ______
