Cell Science Exam - Long Answer Tasks
42 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What induces necro taxis in cells?

  • Concentration gradient of surface molecules
  • Movement induced by chemokines
  • Release of necrotic factors by injured cells (correct)
  • Proteolytic enzyme activity

    • Which statement is true concerning kinases?

  • They phosphorylate amino acids and facilitate signal transduction. (correct)
  • They only regulate the cell cycle.
  • They depolymerize microtubules.
  • They transport GTP across the cell membrane.

    • What effect does colchicine have on microtubules?

  • It stabilizes microtubules.
  • It causes microtubule shortening.
  • It inhibits microtubule assembly. (correct)
  • It promotes microtubule assembly.

    • Which molecule is primarily responsible for the bending of flagella?

    <p>ATPs hydrolysis by dynein</p> Signup and view all the answers

    How does GTP hydrolysis relate to tubulin dynamics?

    <p>It is associated with the depolymerization of tubulin.</p> Signup and view all the answers

    Which of the following statements about mitochondria is correct?

    <p>ATP is synthesized in the mitochondria.</p> Signup and view all the answers

    What role do microtubules play in the cell?

    <p>They help organize the position of organelles.</p> Signup and view all the answers

    Which characteristic is unique to intermediate filaments when compared to microtubules and microfilaments?

    <p>They provide mechanical strength.</p> Signup and view all the answers

    How do microfilaments contribute to cell structure?

    <p>They help control the outer shape of the cell.</p> Signup and view all the answers

    What is a common feature of microfilaments, microtubules, and intermediate filaments?

    <p>They are dynamic structures aiding in movement and stability.</p> Signup and view all the answers

    What is one of the functions of the smooth endoplasmic reticulum (sER)?

    <p>Synthesis of membrane lipids</p> Signup and view all the answers

    Which of the following is NOT a criterion of terrestrial life?

    <p>Varied diet</p> Signup and view all the answers

    What is a significant aspect of the RNA world theory?

    <p>RNA is a substance of inheritance</p> Signup and view all the answers

    What is the role of the nuclear pore complexes (NPC)?

    <p>Regulate the exchange of molecules</p> Signup and view all the answers

    Why is stem cell research important for regenerative medicine?

    <p>They can differentiate into various cell types</p> Signup and view all the answers

    What happens during N-glycosylation?

    <p>Oligosaccharide chains are modified</p> Signup and view all the answers

    What is a function of the rough endoplasmic reticulum (rER)?

    <p>Transport of proteins to the Golgi</p> Signup and view all the answers

    How do stem cells assist in disease modeling?

    <p>By mimicking affected cell types</p> Signup and view all the answers

    What role do myosin motor proteins play in relation to actin filaments?

    <p>They transport vesicles along actin filaments.</p> Signup and view all the answers

    What is the function of Bcl-2 in cellular processes?

    <p>It is an anti-apoptotic protein.</p> Signup and view all the answers

    How are Okazaki fragments dealt with during DNA replication?

    <p>They are joined by DNA ligase.</p> Signup and view all the answers

    What process do developing neurons undergo when competing for survival factors?

    <p>Apoptosis.</p> Signup and view all the answers

    What is the primary function of calmodulin in cells?

    <p>To regulate intracellular Ca2+ concentration.</p> Signup and view all the answers

    What is true about the diameter of nucleosome core particles?

    <p>They measure 30nm in diameter.</p> Signup and view all the answers

    What can be stated about the movement of glycolipids in membrane compartments?

    <p>They switch sides of the lipid bilayer via flippase activity.</p> Signup and view all the answers

    Which statement about microtubules is correct in the context of DNA replication?

    <p>They play no role in DNA replication processes.</p> Signup and view all the answers

    What is the primary characteristic of stem cells?

    <p>They have the ability to differentiate into specialized cell types and self-renew.</p> Signup and view all the answers

    Which type of stem cells can become any cell type in the body?

    <p>Embryonic stem cells</p> Signup and view all the answers

    What ethical concern is associated with the use of embryonic stem cells?

    <p>Their derivation often involves the destruction of embryos.</p> Signup and view all the answers

    What is a function of induced pluripotent stem cells (iPSCs)?

    <p>They are created by treating adult cells to regain embryonic-like properties.</p> Signup and view all the answers

    What is NOT a physical parameter important for cell culturing?

    <p>Color of the medium</p> Signup and view all the answers

    What is the role of calmodulin in cellular processes?

    <p>It modifies target proteins based on Ca2+ concentration.</p> Signup and view all the answers

    Which of the following is NOT a cell morphological change induced by pro-apoptotic factors?

    <p>Nuclear enlargement</p> Signup and view all the answers

    What does chemotaxis refer to in cellular biology?

    <p>Cell movement in response to a concentration gradient of a molecule.</p> Signup and view all the answers

    Which function is NOT associated with peroxisomes?

    <p>Synthesises ATP</p> Signup and view all the answers

    What is the origin of the peroxisome according to the endosymbiotic theory?

    <p>Developed through the engulfment of free-living bacteria</p> Signup and view all the answers

    Which statement accurately describes the role of the GTP-bound alpha subunit in G protein signaling?

    <p>It activates downstream molecules such as adenylyl cyclase</p> Signup and view all the answers

    What differentiates symport proteins from antiport proteins?

    <p>Symports transport substances in the same direction, antiports do so in opposite directions</p> Signup and view all the answers

    Which of the following statements is correct about the mechanism of transporters compared to channels?

    <p>Channels allow solutes to cross membranes more rapidly than transporters</p> Signup and view all the answers

    Which aspect is NOT true regarding the G protein signaling mechanism?

    <p>Nucleotide-free beta-gamma complex activates downstream molecules</p> Signup and view all the answers

    What metabolic function is performed by peroxisomes that aids in fatty acid metabolism?

    <p>Catabolise branched fatty acids</p> Signup and view all the answers

    Which process happens primarily in the rough endoplasmic reticulum (rER)?

    <p>Protein synthesis and modification</p> Signup and view all the answers

    Study Notes

    Cell Science Exam - Long Answer Tasks

    • Actin Filaments and Vesicle Transport: Actin filaments provide tracks for myosin motor proteins to transport vesicles, enabling intracellular transport and organization.

    • Bcl-2 and Apoptosis: Injection of Bcl-2 into a cell prevents apoptosis, as Bcl-2 is an anti-apoptotic protein regulating the mitochondrial pathway of apoptosis.

    • Okazaki Fragments and RNA: Okazaki fragments are short DNA fragments produced during lagging strand replication. DNA ligase joins these fragments, nucleases degrade RNA, not Okazaki fragments.

    • Microtubules and DNA Replication: Microtubules are not involved in DNA replication, but rather in cell division and other cellular processes.

    • Developing Neuron Survival and Necroptosis: Developing neurons compete for survival factors; those that do not acquire sufficient factors undergo apoptosis, not necroptosis.

    • Calmodulin and Calcium Regulation: Calmodulin is a calcium-binding protein crucial for regulating intracellular calcium levels.

    • Nucleosome Core Particles and Filaments: Nucleosome core particles are 30nm in diameter. Nucleosome filaments condense DNA, but filaments are not 30nm.

    Cell Science Exam - Additional Concepts

    • Peroxisome Functions: Peroxisomes have various functions including catalysing hydrogen peroxide, breaking down fatty acids, amino and branched acids and reducing oxygen species.

    • Peroxisome Origin: The peroxisome evolved through an endosymbiotic relationship, likely engulfing a bacterium capable of oxidative reactions. It is part of the endomembrane system (with the ER).

    • GTP-Bound G-Proteins and GPCRs: GTP-bound alpha subunits directly affect downstream molecules (such as adenylyl cyclase); nucleotide-free beta-gamma complexes are inactive.

    • Membrane Transport (Transporters and Channels): Transporters often require ATP for movement while Channels move substances faster due to passive transport through a direct passage.

    • Symporters and Antiporters: Symporters move substances in the same direction; antiporters move substances in opposite directions; reversing the orientation disrupts transport.

    • Rough Endoplasmic Reticulum (rER) Functions: rER is responsible for polypeptide folding, N-glycosylation, quality control, and transport of proteins to the Golgi via vesicles.

    • Smooth Endoplasmic Reticulum (sER) Functions: sER functions include synthesis of membrane lipids, steroid synthesis, calcium storage and detoxification.

    • RNA World Theory: RNA acts as an inheritable substance, can catalyze its own replication, and its synthesis is simpler than DNA’s.

    • Nuclear Lamina and Nuclear Envelope: The nuclear lamina is connected to the outer nuclear membrane via nuclear pores, regulating the exchange of molecules between nucleus and cytoplasm. The lamina is associated with the inner nuclear membrane.

    • Stem Cell Research: Stem cell research applies to regenerative medicine due to their ability to differentiate, offering a potential for repairing damaged tissues and organs.

    • Stem Cells (Embryonic and Adult): Embryonic stem cells are derived from embryos and are pluripotent—capable of differentiating into any cell type. Adult stem cells differentiate into a limited number of cell types.

    • Cell Culturing: Essential parameters for cell culturing include appropriate temperature, oxygen/carbon dioxide levels, humidity, osmolarity, pH, aseptic conditions, proper cell density, co-culture and feeder cell layers , and appropriate chemically defined media with specific components including hormones and serum.

    • Calmodulin: Calmodulin is a Ca2+-binding protein that modifies target proteins based on Ca2+ concentration.

    • Pro-apoptotic Factor-Induced Changes: Pro-apoptotic factors trigger cellular shrinkage, nuclear condensation/fragmentation, membrane blebbing, and loss of plasma membrane integrity.

    • Cellular Movement: Chemotaxis is directed movement based on concentration gradients. Necrotaxis is towards necrotic factors. Chemokinesis is random movement impacted by concentration gradients. Haptotaxis or mesenchymal migration is directed movement following cleavage of ECM components or toward surface molecules.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Cell Science Exam PDF

    Description

    Test your understanding of key concepts in cell biology with this long answer exam quiz. Explore important topics such as actin filaments, apoptosis, Okazaki fragments, and the role of microtubules in cellular processes. Assess your knowledge of how these elements contribute to cellular function and organization.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser