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100 Cards in this Set
- Front
- Back
Selectins |
A family of integral membrane glycoproteins that recognize and bind to specific arrangements of carbohydrate groups projecting from the surface of other cells. |
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Integral Proteins |
A membrane associated protein that penetrates or spans the lipid bilayer. |
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IgSF Stands for ______ |
Immunoglobin Superfamily |
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Immunoglobin Superfamily (IgSF) |
A wide variety of proteins that contain domains of amino acids that are homologous to domains that make up the polypeptide chains of blood-borne antibodies. |
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Selectins |
Found in leukocytes, platelets, and endothelial cells, mediate non-junctional interactions. |
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Immunoglobulin Domains |
Members of the IgSF used to mediate calcium independent nonfunctional cell-cell interactions. |
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Cadherins |
A family of related glycoproteins that mediate Ca2+ dependent cell-cell adhesion and signal transmission from the ECM into the cytoplasm. |
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EMT stands for ______ |
Epithelial Mesenchymal Transition |
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Epithelial Mesenchymal Transition |
A process in which epithelial cells detach from neighboring cells and migrate, forming mesenchymal stem cells. |
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ECM stands for _____ |
Extracellular Matrix |
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Usher Syndrome |
A genetic disorder characterized by hearing and vision impairment. |
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Metastasis |
The spread of cancer cells from a primary tumor to distant sites in the body where a secondary tumor may arise. |
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Zonulae Adherens are also known as _____ |
Adheren's Junction |
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Adheren's Junctions |
A type of specialized adhesive junction particularly common in epithelia. Cadherin molecules are concentrated in the plasma membranes of this region. |
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Adheren's Junctions |
Cells in this region are held together by linkages between the extracellular domains of cadherin molecules that bridge the gap between neighboring cells. |
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Adheren's Junctions |
Occur as a "belt" that encircles each intestinal epithelial cell near its apical surface. Are internally linked to the actin cytoskeleton and mainly provide structural support and continuity. |
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Maculae Adherens are also known as _____ |
Desmosomes |
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Desmosomes |
Disc shaped, "spot welds," (think bedazzler) are adhesive junctions abundant in tissues subject to mechanical stress- skin epithelium, cardiac muscle, etc. |
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Transmembrane Signaling |
Transfer of info across the plasma membrane |
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Tight Junctions |
Specialized contacts (like staples pinching membrane) that occur at the very apical end of the functional complex between cells. The two adjoining membranes are held together by integral membrane proteins. |
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Gap Junctions |
Sites between animal cells that are specialized for intracellular communication. These "pipelines" are composed of connexons. |
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Plasmodesmata |
Cytoplasmic channels that connect most plant cells and extend between adjacent cells directly through the cell wall. |
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Three Types of Cell Adhesion |
Homophilic, heterophilic, and binding through an extracellular linker molecule. |
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Homophilic Adhesion |
Surface molecules on the interacting cells are alike |
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Heterophilic Adhesion |
Surface molecules on the interacting cells are different but complementary. |
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VCAM's stand for _______ |
Vascular cell-adhesion molecules |
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Vascular Cell-Adhesion Molecules |
Important for placental and embryonic circulatory system development AND for mediating neutrophil "rolling" before the invasion. |
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NCAM's stand for ________ |
Neural cell-adhesion molecules |
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NCAM's and L1 |
Both very important to the development of embryonic nervous system, mediating cell-cell interactions and mediating growth cone "creeping" respectively. |
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Catenins |
Proteins in the cytosol that tether cadherins to the cytoskeleton and transmit info into the cytoplasm. |
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Synaptic Junctions |
The means by which a growing axon attaches to its target cells, mediated by protocadherins. |
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Protocadherins |
Members of a unique family of cadherins that contain 6 tandem extracellular domains. These are thought to hold pre- and postsynaptic membranes to facilitate synaptic transmission. |
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Connexons |
An assembly of six proteins called connexins that form the pore for a gap junction between the cytoplasm of two adjacent cells.
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Epithelial Tissue |
Tissue composed of closely packed cells that line spaces within the body |
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Connective Tissue |
Tissue that consists largely of a variety of distinct fibers that interact with each other in very specific ways |
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Glycocalyx |
A layer closely applied to the outer surface if the plasma membrane |
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Functions of the Glycocalyx |
Mediate cell-cell interaction, mediate cell-ECM interactions, provide mechanical protection to the cell, and serve as a barrier |
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Extracellular Matrix |
An organized network of secreted molecules that provide scaffolding to the cells and tissues it surrounds. |
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Functions of the ECM |
Determine the 3D structure of cells and tissues, act as a selectively permeable filter, provide physical and chemical cues to cells, and act as a mineral storage. |
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Basement Membrane |
(=Basal Lamina) A very organized, thickened layer of ECM that surrounds muscle and fat cells, and underlies the basal surface of epithelial cells. |
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Molecules of the ECM |
Collagen, proteoglycans, fibronectin, and laminins. |
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Collagen |
A family of fibrous glycoproteins, produced by fibroblasts as well as smooth muscle and epithelial cells. Known for tensile strength. |
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Type IV Collagen |
Non-fibrillar collagen that forms a lattice structure important for the formation of basement membranes as well as deposition of other ECM materials. |
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Proteoglycans |
A protein polysaccharide complex, found in basement membranes and cartilage. These molecules are capable of binding huge numbers of cations and consequently form a porous hydrating gel that acts as a compression resistant packing material. |
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GAG's stands for _______ |
Glycosaminoglycans |
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HA is ________ |
Hyaluronic Acid |
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Matrix Metalloproteinases |
(=MMP's) A family of zinc-containing enzymes that act in the extracellular space to digest various extracellular proteins and proteoglycans. |
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Integrins |
A super family of integral membrane proteins that bind specifically to extracellular molecules. |
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Fibronectin |
A high-molecular weight glycoprotein that binds to membrane spanning receptor proteins called integrins. |
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RGB Peptides |
(Arganine-glycine-aspartic acid) a sequence of three amino acids that binds specifically to integrins. |
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Laminins |
Family of extracellular matrix glycoproteins that has binding sites for collagen at the ends of its 2 side arms. |
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Integrins mediate _____ |
Binding of cells to the ECM and transmission of signals from the external environment. |
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Focal Adhesion Kinase (FAK) |
A kinase, activated by integrins, involved in cellular adhesion and spreading |
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Focal Adhesions |
Large macromolecules assemblies through which, mechanical force and regulatory signals are transmitted between the ECM and the cell |
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Hemidesmosomes |
Specialized adhesive "stud-like" structures attaching cells to underlying basement membrane |
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Cell Wall |
The homologous ECM structure of plant cells |
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Suberin |
A wax-like substance whose presence effectively forces water in certain directions. |
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Lignin |
A complex network of phenolic compounds that makes cell walls rigid |
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Cell Signaling |
communication in which info is relayed across the plasma membrane to the cell interior, often to the nucleus, by means of a series of cellular interactions. |
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Signal Transduction |
Type of cell signaling in which a signal of one chemical or physical form is recognized at the cell surface and translated into a signal of a different chemical or physical form inside the cell. |
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Receptor |
Any substance that can bind to a specific molecule (ligand) often leading to uptake or signal transduction. |
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Ligand |
Any molecule that can bind to a receptor because of its complementary structure. |
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Effector |
A substance that lies downstream of signal perception and that brings about an intracellular response |
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Second Messenger |
A Substance that is released into the interior of a cell as a result of the binding of a first messenger (ligand) to a receptor |
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Signal Amplification |
The process by which the relatively small scale perception of an external signal becomes a large scale intracellular response. |
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Protein Kinases |
Phosphorylate other proteins thereby affecting their activity/function |
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Protein Phosphatases |
Dephosphorylate other proteins thereby affecting their activity/function |
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GTP-binding Proteins (G-proteins) |
A family of proteins that act as molecular switches inside cells and are involved in transmitting signals from a variety of external stimuli |
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Active G-Proteins |
G-proteins containing bound GTP |
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Inactive G-Proteins |
G-proteins containing bound GDP |
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Accessory proteins that aid in the cycling of GTP |
GTPase Activating Proteins (GAPs), Guanine Nucleotide Exchange Factors (GEFs), and Guanine Nucleotide-Dissociation Inhibitors (GDIs) |
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GAPs |
Shorten the duration of a G-protein mediated response |
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GEFs |
Bind to an inactive G-protein and stimulate the removal of GTP, therefore stimulating G-protein "turnover" |
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GDIs |
Inhibit the release of GDP, therefore maintaining the g-protein in an inactive state |
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Adenylyl Cyclase |
A membrane protein responsible for the synthesis of Cycling AMP (cAMP) |
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Meiosis |
The process in which chromosome number is reduced so that cells are formed that contain only one member of each pair of homologous chromosomes |
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Independent Assortment |
One of Mendel's laws that states that by the end of meiosis, the maternal and paternal chromosomes have been shuffled |
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Genetic Recombination |
Mixing of maternal and paternal alleles that occurs during the first portion of meiosis making the chromosomes passed to offspring not identical to either parent. |
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Stages of Prophase I (in order) |
Leptotene, zygotene, pachytene, diplotene, and diakinesis. |
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Leptotene |
The first stage of prophase I where chromosomes condense and begin to associate with their homologous partner |
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Zygotene |
The second phase of prophase I where synapsis occurs accompanied by the SC providing a scaffold that facilitated genetic recombination |
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Synapsis |
The process by which homologous chromosomes become joined to one another during meiosis |
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Synaptonemal Complex (SC) |
A ladder-like structure composed of three parallel bars with cross fibers that hold homologous pairs of chromosomes in the proper position to allow the continuation of genetic recombination between strands of DNA. |
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Bivalent (Tetrad) |
The complex formed during meiosis by a pair of synapsed homologous chromosomes |
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Chiasmata |
Specific points of attachment between homologous chromosomes of bivalents at sites where the genetic exchanges occured |
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Pachytene |
The third phase of prophase I during which recombination continues and is completely marked by fully formed SC |
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Diplotene |
The fourth phase of prophase I, SC is dissolved and homologous chromosomes are pulled apart |
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Diakinesis |
The fifth and final stage of prophase I, mitotic spindles assemble, the nuclear envelope breaks down and bivalents move towards the metaphase plate. |
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Metaphase I |
Bivalents all line up at the metaphase plate |
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Anaphase I |
Chromosomes move to the opposite poles |
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Telophase I |
The last phase of Meiosis I, the nuclear envelope may or may not reform |
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Prophase II |
The first stage of meiosis II, if the nuclear envelope reforms in telophase I it is now dissolved and chromosomes condense |
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Metaphase II |
The second stage of meiosis II marked by the lining up of chromosomes |
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Protein kinase Mos |
Responsible for vertebrate oocyte arrest in metaphase II, which causes arrest by inhibiting cyclin B |
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Anaphase II |
The third stage of meiosis II, marked by the synchronous splitting of centromeres, allowing the sister chromatids to move towards the opposite poles |
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Telophase II |
The fourth stage of meiosis II, marked by the enclosure of chromosomes within a nuclear envelope |
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Extracellular Messenger Molecules |
The means by which cells communicate with one another |
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PKA Meaning |
Protein Kinase A |
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AKAPs meaning |
A-Kinase Anchoring Proteins |
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AKAPs are |
Accessory proteins that bind PKA molecules to certain sites so that they are in close contact with specific substrates |