Solutions to the Unit 1 Formative Questions in Statement Form- Koncilja
Chakraborty: Introduction to Cell Biology
The process by which fluids can enter into a normal cell is called pinocytosis.
Phagocytosis is the cellular process of engulfing solid particles by the cell membrane to form an internal phagosome. This involves the vesicular internalization of solid particles.
Receptor mediated endocytosis is a process by which cells internalize molecules by the inward budding of plasma membrane vesicles containing proteins with receptor sites specific to the molecules being internalized. What is different about this from phagocytosis is that a specific active event occurs through the binding of a ligand which mediates a cellular response leading to engulfing of the solid particle. This is less likely to involve unwanted particles than phagocytosis. Both phagocytosis and receptor mediated endocytosis are forms of endocytosis.
Exocytosis is the process where the cell directs the contents of secretory vesicles out of the cell membrane.
Vesicular transport is the means of moving contents through vesicles, small bubbles of liquid within the cell. The vesicle is a membrane enclosed sac that stores or transports substances within a cell.
You are not able to see ribosomes under a light microscope. They are very small. Some stuff you can see under a light microscope includes RBCs, bacterium, nucleus, the nucleolus, and more.
Chakraborty Cell Structure and Function
Desmin is found in muscle cells. Desmin is an intermediate filament present in the cytoplasm of all types of muscle cells.
Microtubules are important for chromosome movement during mitosis.
Chakraborty Blood
The hemopoietic stem cells are pluripotential. This means they have the ability to differentiate to become any kind of blood cell. Specifically the pluripotential hematopoietic stem cells produce two types of multipotential hematopoietic stem cells: colony-forming unit-spleen (myeloid cell line) and conoly-forming unit lymphocytes (lymphoid cell line).
The class of the major histocompatibility complex molecules (MHC) that can present antigen tot he helper T-cells is MHC II. The helper T-cell will have a receptor, but the Class II MHC on the macrophage needs antigen fragment to complement the receptor.
Williams Proteins
Hydrogen bonds are usually longer than covalent bonds.
NH3+ and COO- are both present in glycine at a neutral pH.
The configuration of most alpha-carbon atoms of amino acids linked in a peptide bond is trans.
Smas Plasma Membranes
Covalent bonds between phosphate head groups are not involved in the assembly of the phospholipid bilayer.
In the interactions of the RBC membrane with cytoskeleton, glycophorin is an integral membrane protein with a single membrane spanning alpha-helix and is the basis for the MN blood group. Glycophorin is a type of glycoprotein.
The mode of function of the membrane transport protein that is important for insulin-stimulated glucose uptake in adipose tissue is facilitated diffusion.
Cardiotonic steroids directly exert their function by inhibiting primary transporter ATPase ion pumps.
Crissman Epithelial
The secretory units of a compound tubuloacinar gland has a basement membrane surrounding it.
Desmosomes use the cadherin proteins desmoglein and desmocolin to attach two membranes of adjacent cells. Phemphigus vulgaris is an autoimmune disease where antibodies are attached to the cadherin desmoglein, destroying the desmosomes.
Crissman Connective Tissues
Type I collagen is produced by fibrocytes and osteocytes.
Edema is caused by excess water in the extracellular space.
The basement membrane may act as a macromolecular sieve.
Dignam HB and Enzymes
The effector 2,3 biphosphoglycerate binds to hemoglobin in a cavity between the beat subunits through postiitvely charged side chains.
A 55 yr. Old white male brought to ED with pain radiating to left arm and profuse sweating. Lab findings indicate elevated creatine phosphokinase, troponin, and myoglobin. The lab findings are best explained by the release fo creatine phosphokinase, troponin, and myoglobin from cardiac cells.
Oxygen binding to hemoglobin is best described by positively cooperative binding.
Enzymes can promote catalysis by hydrophobic interactions b/w the residues in the ligand binding site and a substrate, by providing proper orientation of enzyme and substrate reactive groups, by forming a covalent bond with the substrate, and by donating to or accepting a proton from the substrate.
Synthetases (ligases) catalyze joining of two reactants in a reaction requiring energy derived from ATP.
On a Line Weaver-Burke plot, the Vmax kinetic constant can be determined from the value on the y intercept and the Km constant can be determined from the x intercept.
Manning TCA
The enzyme that catalyzes an anaplerotic rxn. In the citric acid cycle is pyruvate carboxylase.
Biotin is not required in the pyruvate dehydrogenase and alpha-ketogutarate dehydrogenase reactions. Biotin is pretty big in the reaction involving fatty acid metabolism.
The substrates for the two enzymatic reactions in the TCA which CO2 is liberated are isocitrate and alpha-KG8.
Manning Electron Transport Chain and Oxidative Phosphorylation
The chemiosmotic coupling hypothesis of oxidative phosphorylation proposes that adenosine triphosphate is formed because a proton gradient forms across the inner mitochondrial membrane.
Dinitrophenol uncouples oxidative phosphorylation by dissipating the proton gradient across the inner mitochondrial membrane.
The number of moles of ATP formed per pair of electrons transferred from reduced NADH to oxygen is 2.5.
Crissman Cell Motility
Leukocyte adhesion deficiency results in the inability of leukocytes to enter the extracellular space at infection sites.
De la Serna Cell Cycle
Analysis of a tumor cell line indicates that there is a dramatically increased level in the activity of the transcription factor E2F. The most likely explanation is that a mutation in the domain of RB to which E2F binds occurred. The consequences of which lead to constitutive E2F activity. Remember that RB blocks transcription. When Rb is hyperphosphorylated, the cell cycle is promoted. When Rb is hypophosphorylated, the cell cycle is inhibited.