Description : The site of enzymes directing the metabolic oxidation (respiration), ATP synthesis and considered as power house of cell are (A) Lysosomes (B) Microsomes (C) Mitochondria (D) Golgi apparatus
Last Answer : (C) Mitochondria
Description : Mitochondria are referred to as the ‘powerhouses’ of a cell. This is because they convert food to energy, or ATP, more efficiently than processes which rely on anaerobic, or non-oxygen using, energy production alone. Name the energy production process carried out by mitochondria.
Last Answer : Oxidative phosphorylation.
Description : The chemiosmotic coupling hypothesis of oxidative phosphorylation proposes that adenosine triphosphate (ATP) is formed because (a) a proton gradient forms across the inner membrane (b) there is a ... mitochondrial proteins (d) ADP is pumped out of the matrix into the intermembrane space.
Last Answer : (a) a proton gradient forms across the inner membrane
Description : Which of the following statements are true of oxidants? A. In addition to their pathophysiologic roles in inflammation, injury, and infection, oxidants also have physiologic roles. B. Oxidants may ... involved the catalytic production of superoxide anion (O 2 ) by the enzyme xanthine oxidase.
Last Answer : Answer: ABCD DISCUSSION: Oxidants are reactive oxygen metabolites that have both physiologic and pathophysiologic roles. As potent oxidizing agents, oxidants are involved in cytochrome P ... leukocyte infiltration and activation, causing further tissue damage by the release of cytotoxic proteases
Description : Adenosine Triphosphate (ATP) is (a) an enzyme (b) a protein (c) a hormone (d) a molecule with high energy bonds
Last Answer : Ans:(d)
Description : The use and transfer of energy in all cells involves the same compound, ATP. The letters ATP stand for the chemical: a) atrophine trichloride b) aluminum trioxide c) adenosine triphosphate d) none of the above
Last Answer : ANSWER: C -- ADENOSINE TRIPHOSPHATE
Description : Why can mitochondria be considered the power plants of the aerobic cells ?
Last Answer : Mitochondria are the power plants of aerobic cells because within them the final stages of the cellular respiration process occurs. Cellular respiration is the process of using organic molecule (mainly ... of the cellular respiration take place: the Krebs cycle and the respiratory chain.
Description : Tissues are constructed from many distinct cell types that perform different functions in response to signals from each other and the extracellular matrix. During tissue development and tissue regeneration, ... that stem cells undergo when they are required to generate a particular type of cell?
Last Answer : Asymmetric cell division. After asymmetric division, each of the two resulting daughter cells has a unique life course. For example, one daughter cell may differentiate into a specific cell type ( ... cell), whereas the other daughter cell may remain a stem cell with unlimited proliferative ability.
Description : What part of the cell serves as the intracellular highway? (A) Endoplasmic reticulum (B) Golgi apparatus (C) Cell membrane (D) Mitochondria
Last Answer : (A) Endoplasmic reticulum
Description : Plant cells contain the following 3 things not found in animal cells _________, _____________ and ______________. (A) Plastids / Chlorophyll / Membrane (B) Chloroplast / Cell wall / Golgi body (C) Plastids / Cell wall / Chlorophyll (D) Mitochondria / Cell wall /
Last Answer : (C) Plastids / Cell wall / Chlorophyll
Description : Hydrogen peroxide degradation in a cell is a function of (A) Ribosomes (B) Mitochondria (C) Peroxisomes (D) Glyoxisomes
Last Answer : mitochondria
Description : List several side-to-side cellular junctions that can influence cell signaling.
Last Answer : Gap junctions, desmosomes, adherens junctions, integrin connections
Description : Eukaryotic cells have extensive intracellular membranes, termed the endomembrane system, which divide the cell into structurally and functionally distinct compartments, or organelles. These include the inner cell ... . Name a cellular component whose membrane is not part of the endomembrane system.
Last Answer : Mitochondria; also chloroplasts
Description : Isolation of cellular components to determine their chemical composition is called (A) Cell differentiation (B) Chromatography (C) Cell fractionation (D) All of these
Last Answer : (C) Cell fractionation
Description : 5’-Terminus of mRNA molecule is capped with (A) Guanosine triphosphate (B) 7-Methylguanosine triphophate (C) Adenosine triphosphate (D) Adenosine diphosphate
Last Answer : Answer : B
Description : What is the endosymbiotic hypothesis about the origin of mitochondria ?
Last Answer : What are the molecular facts that support the hypothesis? To which other cellular organelles the hypothesis can also be applied? It is presumed that mitochondria were primitive aerobic prokaryotes that were ... because they have own DNA, RNA and ribosomes and they can self-replicate too.
Description : What are mitochondria ?
Last Answer : What is the basic morphology of these organelles and in which cells can they be found? Mitochondria are the organelles in which the most important part of the cellular respiration occurs: ... and ribosomes, mitochondria can self-replicate. Cell Structure Review - Image Diversity: mitochondria
Description : Name two unique features of mitochondria.
Last Answer : Surrounded by two membranes (an inner and an outer membrane); have their own genome
Description : Infoldings of inner membrane in mitochondria are called (A) Grana (B) Thyallkoids (C) Cristae (D) Frets
Last Answer : (C) Cristae
Description : Which of the following is NOT a membranous organelle? (A) Lysosomes (B) Peroxisomes (C) Centrioles (D) Mitochondria
Last Answer : (C) Centrioles
Description : What is meant by cellular secretion ?
Last Answer : Cell secretion is the elimination to the exterior of substances produced by the cell (for example, hormones, mucous, sweat, etc.)
Description : List several general cellular processes regulated by receptor tyrosine kinases (RTKs).
Last Answer : Cell growth, cell differentiation and cell survival (i.e. nutrient and stress signaling).
Description : Why do ion channels contribute to faster cellular responses than other signaling mechanisms, such as GPCR-mediated signaling?
Last Answer : Ion channels generate electrical signals, which signals travel much more rapidly than chemical signals that depend on the process of molecular diffusion. An electrical signal can traverse the entire length of a nerve cell within milliseconds.
Description : What are the three major components of glycerophospholipids, the main component of lipid bilayers that comprise cellular membranes?
Last Answer : Glycerol, a phosphate group, fatty acid chains
Description : Which of the following correctly matches an organelle with its function? (A) Mitochondrion . . . photosynthesis (B) Nucleus . . . cellular respiration (C) Ribosome . . . manufacture of lipids (D) Central vacuole . . . storage
Last Answer : (D) Central vacuole . . . storage
Description : The electron transport chain within the inner mitochondrial membrane creates a gradient of ____________ across the inner membrane which is utilized to drive the activity of ATP synthase and the generation of ATP.
Last Answer : Hydrogen (H+ ions) or protons
Description : Select the alternative giving correct identification and function of the organelle A' in the diagram. (a) Mitochondria - Produce cellular energy in the form of ATP (b) Golgi body - ... packaging material (c) Lysosomes - Secrete hydrolytic enzymes (d) Endoplasmic reticulum - Synthesis of lipids
Last Answer : (a) Mitochondria - Produce cellular energy in the form of ATP
Description : Chromatin has two different regions, euchromatin and heterochromatin. One of these regions is highly condensed and considered an inactive region whereas the other is less condensed so it is more ... for transcription. Which of these regions would contain genes that are being transcribed often?
Last Answer : Euchromatin. Euchromatin is less condensly packaged allowing for easier access by transcription factors and polymerases. Heterochromatin is a region of condensed packaging and considered an inactive region.
Description : Which is correct about cell theory in view of current status of our knowledge about cell structure? (a) It needs modification due to discovery of subcellular structures like chloroplasts and ... Cell theory means that all living objects consists of cells whether or not capable of reproducing
Last Answer : (c) Cell theory does not hold good because all living beings (e.g., viruses) do not have cellular organisation.
Description : What are integrins and do they influence cell-cell signaling?
Last Answer : Integrins are a diverse family of transmembrane proteins consisting of alpha and beta subunits that are found in all animal cells. Integrins link the actin cytoskeleton to the ... movement, and can thus influence actin cytoskeleton dynamics and intracellular signaling of neighboring cells.
Description : What are gap junctions and how do they contribute to cell-cell signaling?
Last Answer : Gap junctions are specialized connections that form a pore between adjacent cells, which permit small molecules and ions to move from one cell to another. In this way, gap junctions provide metabolic and electrical coupling between cells.
Description : Metabolism is carried out by a large class of proteins that decrease the activation energy required for chemical reactions inside a cell. Therefore they only facilitate reactions that would naturally occur at a much slower rate. What is the name of these proteins that speed up biochemical reactions?
Last Answer : Enzymes
Description : RNA transcription is more complex in eukaryotes because it is first made as a primary RNA transcript that contains intron and exon sequences. What kind of modification must occur to produce a mature mRNA?
Last Answer : RNA splicing. Introns must be removed and exons are spliced together to form a mature RNA transcript.
Description : Methylxanthines exert the following action (s) at cellular/molecular level (a) Intracellular release of Ca2+ (b) Antagonism of adenosine (c) Inhibition of phosphodiesterase (d) All of the above
Last Answer : Ans: D
Description : Match the following columns and select the correct option. Column-I Column-II (A) Bt cotton (i) Gene therapy (B) Adenosine (ii) Cellular defence deaminase deficiency (C) RNAi (iii) Detection of HIV infection (D) PCR (iv) Bacillus ... (i) (iv) (c) (ii) (iii) (iv) (i) (d) (i) (ii) (iii) (iv)
Last Answer : (a) (iv) (i) (ii) (iii)
Description : Methylxanthines exert the following action(s) at cellular/molecular level: A. Intracellular release of Ca2+ B. Antagonism of adenosine C. Inhibition of phosphodiesterase D. All of the above
Last Answer : D. All of the above
Description : Write a note on ATP (Adenosine Tri-Phosphate). -Biology
Last Answer : answer:
Description : In the phase when the cell is not dividing ?
Last Answer : interphase) is there activity within the cell nucleus? In the interphase there is intense metabolic activity in the cell nucleus: DNA is duplicating, euchromatin is being transcript and RNA is produced.
Description : What is the main cell organelle involved in cell digestion ?
Last Answer : What are the properties of that organelle that enable it to the task? The organelles responsible for intracellular digestion are the lysosomes. Lysosomes are vesicles that contain digestive enzymes ... digested and then digestion takes place. Cell Digestion Review - Image Diversity: lysosomes
Description : Which cell organelles are well-developed in secretory cells ?
Last Answer : In secretory cells, like the secretory cells of endocrine glands, organelles related to production, processing and exportation of substances are widely present and well-developed. These ... protein synthesis between the cytoplasm and the nucleus. Rough endoplasmic reticulum Golgi apparatus
Description : What are cell movements ?
Last Answer : How are these movements created? Cell movements are movements performed by cell structures, like the movements of cilia and flagella, the pseudopod movements (in amoeba, macrophages, etc. ... action, by differences of viscosity among cytoplasmic regions and by intracellular contraction systems.
Description : The cell that expanded itself to this point is called turgid cell ?
Last Answer : Cell Membrane Review - Image Diversity: plasmolysed cell flaccid cell turgid cell
Description : What is meant by suction force of the plant cell ?
Last Answer : Does the suction force facilitate or make difficult the entrance of water in the cell? The suction force (SF) is the osmotic pressure of the plant cell vacuole, i.e., of the vacuolar internal ... vacuole the cytosol becomes hypertonic in relation to the exterior and more water enters the cell.
Description : How does the plant cell wall react when it is placed under hypotonic medium ?
Last Answer : The plant cell wall (the covering of the cell external to the cell membrane) is made of cellulose, a polymer of glucose. When the cell is put under hypotonic medium it absorbs too ... compensate the osmotic pressure thus forbiding excessive increase of the cellular volume and the cell lysis.
Description : What is mass transportation across the cell membrane ?
Last Answer : Mass transportation is the entrance or the exiting of substances in or from the cell engulfed by portions of membrane. The fusion of internal substance-containing membranous vesicles with the cell ... cell after they have been engulfed by projections of the membrane is called endocytosis.
Description : How does the sodium-potassium pump present in the cell membrane work ?
Last Answer : What is the importance of this protein for the cell? The sodium-potassium pump is the transport protein that maintains the concentration gradient of these ions between the intra and the ... maintain the cellular metabolism. Cell Membrane Review - Image Diversity: sodium-potassium pump
Description : What are differentiations of the cell membrane ?
Last Answer : In some types of cells, the cell membrane present differentiations that are necessary for the specific functions of the cells. The main differentiations are the microvilli and the structures for ... tight junctions (zonula occludens), zonula adherens (adherens junctions) and gap junctions.
Description : What are the basic constituents of the cell membrane ?
Last Answer : The cell membrane is formed of lipids, proteins and carbohydrates. The membrane lipids are phospholipids, a special type of lipid to which one extremity a phosphate group is bound thus ... cell membrane. Cell Membrane Review - Image Diversity: phospholipid bilayer membrane proteins glycocalyx
Description : Concerning permeability what type of membrane is the cell membrane ?
Last Answer : The cell membrane is a selectively permeable membrane, i.e., it allows the passage of water and some selected solutes. Cell Membrane Review - Image Diversity: cell membrane
Description : What are plant cell vacuoles ?
Last Answer : What are their functions? How is the covering membrane of the vacuoles called? Plant cell vacuoles are cell structures delimited by membranes within which there is an aqueous solution made of ... delimits the vacuoles is called tonoplast, named after the osmotic function of the structure.