Term
| All eukaryotic cells are composed of three parts |
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Definition
1. plasma membrane
2. cytoplasm
3. nucleus |
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Term
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Definition
| a gelatin-like substance, plus structural fibers and organelles (but not the nucleus) |
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Term
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Definition
| contains the genetic library of the cell |
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Term
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Definition
controls passage of materials in and out of cell (semi-permeable, selectively permeable).
-intercellular face-side faces cytoplasm.
-extracellular face-side faces outwards
controls interactions/communication with other cells(sensitivity)
-identification
-protection
-adhesion |
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Term
| Lipids constitute ______ of the plasma membrane |
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Definition
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Term
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Definition
Phospholipid bilayer
-75% of the lipids
-hydrophilic heads (phosphate) on each side
-hydrophobic tails in the center |
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Term
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Definition
Cholesterol
-affects membrane fluidity (makes bilayer stronger but less fluid at body temp, and has opposite effect at low temps |
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Term
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Definition
| -Glycolipids: found only on extracellular face, contriubte to glycocalyx (carbohydrate coating on cell surface, act as a molecular signal so that cells can recognize one another). |
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Term
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Definition
integral proteins contribute to the moelcules found in the plasma membrane.
-transmembrane proteins
--pass completely through membrane
--most are glycoproteins
peripheral proteins: adhere to the inner or outer surface of the membrane |
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Term
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Definition
| membrane proteins with a carbohydrate group attached that protrude int the extracellular fluid. |
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Term
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Definition
| entire "sugary coating" surrounding the membrane (made up of the carbohydrate portions of the glycolipids and glycoproteins). |
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Term
| membrane protein function |
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Definition
pores, ion channels, carrier/transporters, pumps(semi-permeable)
receptors, identity(sensitivity), adhesion, messanger systems, enzymes |
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Term
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Definition
| allows specific ion to move through water-filled pore. most plasma membranes include specific channels for several common ions |
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Term
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Definition
| carries specific substances across membrane by changing shape. for example, amino acids, needed to synthesize new proteins, enter body cells via new carriers. Carrier proteins are also known as transporters. |
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Term
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Definition
| recognizes specific ligand and alters cell's function in some way. for example, antidiuretic hormone binds to receptors in the kidneys and changes of water permeability of certain plasma membrane |
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Term
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Definition
movement of particles across membrane from area of high concentration to an area of low concentration (down or with the concentration gradient).
-small uncharged solutes(most gases and lipids) |
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Term
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Definition
-proteins allow solutes across cell membrane(like a door)
-solutes still move down concentration gradient
--charged particles (ions, amino acids, nucleotides) |
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Term
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Definition
movement of water through a selectively permeable membrane
-from an area of more water to an area of less water
-from an area of less solutes to an are of more solutes
-aquaporins are channel proteins in cell membrane that allow water to move freely in our out of the cell, and is determined by the tonicity (salt concentration) of the solution |
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Term
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Definition
protein-mediated, active transport of solute goes across membrane against its concentration gradient.
-energy (usually atp) required
-prominent example is the sodium-potassium pump
-3 Na+ out/ 2K+ in/ 1 ATP used |
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Term
primary vs secondary active transport
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Definition
primary: -aka dependent
-directly uses energey from atp
secondary:-aka atp-independent
-uses energy from ion gradients (usually na+)
-the gradient along atp |
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Term
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Definition
carry two substances across the membrane in opposite directions.
-secondary active transport mechanism |
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Term
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Definition
carry two substances across the membrane in the same direction.
-secondary active transport mechanisms |
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Term
| bulk(vesicular transport) |
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Definition
transport of large particles or fluid droplets through membrane in bubble-like vessicles of plasma membrane, uses atp.
-endocytosis and exocytosis |
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Term
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Definition
| vesicular transport out of the cell |
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Term
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Definition
vesicular transport into cell
-phagocytosis: engulfing large particles |
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Term
| organelles specialized structures within the cell |
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Definition
-ribosomes
-endoplasmic reticulum(smooth and rough)
-golgi complex
-lysosomes
-mitochondria
-nucleus |
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Term
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Definition
intracellular fluid, sorrounding the organelles.
-cytoskeleton |
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Term
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Definition
| network of protein filaments throughout the cytosol, provides structural support for the cell |
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Term
| types in the cytoskeleton |
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Definition
microfilaments
intermediate filaments
microtubules |
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Term
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Definition
| a dense network of small protein fibers locates near the nucleus of a cell, consists of two centrioles and a pericentrioler material |
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Term
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Definition
| a dense network of small protein fibers located near the nucleus of a cell, consists of two centrioles and pericentriolar material |
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Term
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Definition
| short, hair like projections from the cell surface, move fluids along a cell surface |
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Term
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Definition
| longer than cilia, move an entire cell, only example is the sperm cell's tail |
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Term
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Definition
| a cellular structure composed of a small subunit and a large subunit that contain ribsomal rna and ribosomal proteins; sites of protein synthesis |
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Term
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Definition
| network of membranes or channels that serve in intracellular transporation, support, storage, synthesis, and packing of molecules |
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Term
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Definition
| portions where the surface is studded with ribosomes, produces various proteins |
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Term
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Definition
| portions where the surface does not have ribosomes, synthesizes fatty acids and steroids, detoxifies certain drugs |
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Term
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Definition
consists of 3-20 flattened, membranous sacs called cisternae.
-accepts proteins from rough ER
-modify, sort, and package proteins for transport to different destinations |
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Term
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Definition
| vesciles that form from the golgi complex and contain powerful digestive enzymes |
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Term
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Definition
spherical or oval shaped structure
-usually most prominent feature of a cell
-nuclear envelope: a double membrane that seperates the nucleus from the cytoplasm
-nuclear pores: numerous openings in the nuclear envelope, control movement of substances between nucleus and cytoplasm
-nucleolus: spherical body that produces ribosomes and chromosomes |
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