Prokaryote vs. Eukaryote Cells Quiz
34 Questions
0 Views

Prokaryote vs. Eukaryote Cells Quiz

Created by
@ReplaceableWashington9913

Podcast Beta

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which structure is characteristic of prokaryotic cells?

  • Organelles like mitochondria
  • Nuclear membrane
  • Complex endoplasmic reticulum
  • Mesosome (correct)

    • What distinguishes Gram positive bacteria from Gram negative bacteria?

  • Ability to take up gram stain (correct)
  • Thickness of the glycocalyx
  • Presence of a plasma membrane
  • Presence of ribosomes

    • Which of the following statements is true regarding the cell envelope of prokaryotic cells?

  • It primarily provides energy for the cell.
  • It contains three distinct layers. (correct)
  • It is a loosely constructed structure.
  • It consists of a single layer of plasma membrane.

    • What is the function of the plasma membrane in prokaryotic cells?

    <p>To selectively control interactions with the external environment</p> Signup and view all the answers

    Which structure determines the shape of a prokaryotic cell?

    <p>Cell wall</p> Signup and view all the answers

    What can the glycocalyx of bacteria vary in?

    <p>Composition and thickness</p> Signup and view all the answers

    What is the primary role of the outermost layer of the cell envelope in prokaryotes?

    <p>To protect against environmental stress</p> Signup and view all the answers

    Which statement accurately describes ribosomes in prokaryotic cells?

    <p>They are the only organelles found in prokaryotic cells.</p> Signup and view all the answers

    What is the primary lipid component of the cell membrane?

    <p>Phospholipids</p> Signup and view all the answers

    Which statement correctly describes the arrangement of phospholipids in the cell membrane?

    <p>Polar heads towards the outer sides and hydrophobic tails towards the interior</p> Signup and view all the answers

    What distinguishes integral proteins from peripheral proteins in cell membranes?

    <p>Integral proteins are entirely within the membrane structure</p> Signup and view all the answers

    What important model describes the structure of the cell membrane proposed by Singer and Nicolson?

    <p>Fluid mosaic model</p> Signup and view all the answers

    What role does the fluid nature of the cell membrane play in cell functions?

    <p>It allows proteins to move laterally for various functions</p> Signup and view all the answers

    Which component contributes to the stability and fluidity of the cell membrane?

    <p>Cholesterol</p> Signup and view all the answers

    What percentage of the cell membrane in human erythrocytes is made up of proteins?

    <p>52%</p> Signup and view all the answers

    What is a vital function of the plasma membrane according to its structure?

    <p>Transport of molecules across the membrane</p> Signup and view all the answers

    Which organelles are included in the endomembrane system?

    <p>Endoplasmic reticulum and lysosomes</p> Signup and view all the answers

    What characterizes rough endoplasmic reticulum (RER)?

    <p>It has ribosomes attached to its outer membrane.</p> Signup and view all the answers

    What is the primary role of smooth endoplasmic reticulum (SER)?

    <p>Lipid synthesis and steroid hormone production.</p> Signup and view all the answers

    Which statement is true regarding the endomembrane system?

    <p>Components of the endomembrane system have coordinated functions.</p> Signup and view all the answers

    Who first observed the structures later named Golgi bodies?

    <p>Camillo Golgi</p> Signup and view all the answers

    What is a primary distinguishing feature of the endoplasmic reticulum?

    <p>It divides intracellular space into luminal and extra luminal compartments.</p> Signup and view all the answers

    Which of the following organelles is not part of the endomembrane system?

    <p>Ribosomes</p> Signup and view all the answers

    What function do lysosomes primarily serve within the endomembrane system?

    <p>Digest macromolecules and waste materials.</p> Signup and view all the answers

    What is the configuration of the centrioles within a centrosome?

    <p>They lie perpendicular to each other.</p> Signup and view all the answers

    What structure is formed by the central part of the proximal region of a centriole?

    <p>The hub.</p> Signup and view all the answers

    What primarily composes the peripheral triplets of a centriole?

    <p>Fibrils of tubulin protein.</p> Signup and view all the answers

    What role do centrioles play during cell division in animal cells?

    <p>Generating spindle fibers.</p> Signup and view all the answers

    Who first described the nucleus as a cell organelle?

    <p>Robert Brown.</p> Signup and view all the answers

    What is the primary component of ribosomes?

    <p>Ribonucleic acid (RNA) and proteins</p> Signup and view all the answers

    Which of the following correctly distinguishes eukaryotic and prokaryotic ribosomes?

    <p>Eukaryotic ribosomes are larger than prokaryotic ribosomes.</p> Signup and view all the answers

    What are the two subunit sizes of eukaryotic ribosomes known as 80S?

    <p>60S and 40S</p> Signup and view all the answers

    What is the primary function of the cytoskeleton in a cell?

    <p>Mechanical support and maintenance of cell shape</p> Signup and view all the answers

    Which of the following statements about ribosomes is incorrect?

    <p>Ribosomes are surrounded by a membrane.</p> Signup and view all the answers

    Study Notes

    Prokaryote vs. Eukaryote Cells

    • Prokaryotic cells are typically smaller (0.02-0.2 mm) than eukaryotic cells (10-20 mm)
    • Eukaryotes have a nucleus, a cell membrane, and organelles, while prokaryotes do not have a nucleus, only have ribosomes as organelles, and have a unique mesosome
    • Plasmids are used to monitor the transformation of bacteria with foreign DNA

    Cell Envelope

    • Most prokaryotic cells have a cell envelope consisting of a glycocalyx, cell wall, and plasma membrane
    • The cell envelope acts as a protective unit
    • Classification of bacteria is based on differences in their cell envelopes and staining properties: Gram-positive and Gram-negative
    • Glycocalyx can be loose (slime layer) or thick and tough (capsule)
    • The cell wall provides structural support and helps prevent the bacteria from bursting or collapsing
    • The plasma membrane interacts with the external environment and is selectively permeable

    Plasma Membrane

    • The plasma membrane is composed of lipids and proteins
    • The major lipids are phospholipids that are arranged in a bilayer with polar heads facing outward and hydrophobic tails facing inward
    • Cholesterol is also present in the membrane
    • Membrane proteins can be integral or peripheral
    • Integral proteins are embedded in the membrane, while peripheral proteins are only on the surface
    • The fluid mosaic model proposed by Singer and Nicolson in 1972 describes the structure of the cell membrane: the membrane is fluid and proteins can move laterally within it
    • The fluidity of the membrane is essential for several functions such as growth, intercellular junctions, secretion, endocytosis, and cell division

    Endomembrane System

    • The endomembrane system includes: ER, Golgi complex, lysosomes, and vacuoles
    • Mitochondria, chloroplast, and peroxisomes are not part of the endomembrane system
    • The endomembrane system functions are coordinated

    Endoplasmic Reticulum (ER)

    • ER is a network of tiny tubular structures scattered in the cytoplasm
    • It divides the intracellular space into luminal (inside ER) and extraluminal (cytoplasm) compartments
    • RER has ribosomes attached to its outer surface
    • SER lacks ribosomes
    • RER is involved in protein synthesis and secretion
    • SER is the site of lipid synthesis, including steroidal hormones in animal cells

    Golgi Apparatus

    • Golgi bodies are densely stained reticular structures near the nucleus
    • They are involved in the processing and packaging of proteins and lipids
    • They consist of flattened membrane-bound sacs called cisternae

    Mitochondria

    • Mitochondria are double membrane-bound organelles
    • They are the sites of cellular respiration and ATP production
    • The inner membrane of mitochondria is folded into cristae, which increases surface area for ATP production

    Lysosomes

    • Lysosomes are membrane-bound vesicles that contain hydrolytic enzymes
    • They are involved in the degradation of cellular waste materials, foreign substances, and worn-out organelles
    • Lysosomes have a role in autophagy (self-eating) and apoptosis (programmed cell death)

    Vacuoles

    • Vacuoles are large membrane-bound sacs that occupy a significant portion of the plant cell volume
    • They are involved in storage of water, nutrients, and waste products
    • Vacuoles also help maintain turgor pressure in plant cells

    Chloroplasts

    • Chloroplasts are double membrane-bound organelles found in plant cells
    • They contain chlorophyll pigments and are the sites of photosynthesis
    • They have a third membrane system called thylakoids, which are stacked into grana
    • Chloroplasts have their own DNA (circular) and ribosomes (70S)

    Ribosomes

    • Ribosomes are granular structures composed of RNA and proteins
    • They are not surrounded by a membrane
    • Eukaryotic ribosomes are 80S, and prokaryotic ribosomes are 70S
    • Each ribosome has two subunits: a larger and a smaller subunit
    • Ribosomes are the sites of protein synthesis

    Cytoskeleton

    • The cytoskeleton is a network of filamentous proteinaceous structures present in the cytoplasm
    • It includes microtubules, microfilaments, and intermediate filaments
    • It provides mechanical support, enables motility, and maintains cell shape

    Centrosome and Centrioles

    • The centrosome is an organelle that usually contains two cylindrical structures called centrioles
    • Centrioles are made up of nine peripheral fibrils of tubulin protein arranged in triplets
    • The centrioles form the basal bodies of cilia and flagella, and spindle fibers during cell division in animal cells

    Nucleus

    • The nucleus was first described by Robert Brown in 1831
    • The nuclear material stained by basic dyes was named chromatin by Flemming
    • The interphase nucleus contains chromatin, nuclear matrix, and one or more nucleoli
    • The nucleus is the control center of the cell, containing the cell's genetic material (DNA)
    • The nucleus is involved in the regulation of gene expression and cell division

    Studying That Suits You

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

    Quiz Team

    Related Documents

    Cell: Structure And Functions PDF

    Description

    Test your knowledge of the differences between prokaryotic and eukaryotic cells, including their structure and function. This quiz covers key concepts such as cell envelopes, plasma membranes, and classification based on cell structures. Perfect for biology students looking to reinforce their understanding.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser