Cell Biology: Eukaryotic and Prokaryotic Cells
40 Questions
3 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 is the fundamental difference between prokaryotic and eukaryotic cells?

  • Eukaryotic cells contain a nucleus. (correct)
  • Prokaryotic cells have membrane-bound organelles.
  • Prokaryotic cells possess multiple chromosomes.
  • Eukaryotic cells are generally smaller.

    • Which of the following correctly describes prokaryotic cells?

  • They contain a well-defined nucleus.
  • They have DNA enclosed within a nucleus.
  • They lack membrane-bound organelles. (correct)
  • They are typically larger than eukaryotic cells.

    • What condition may cause a human cell to have 47 chromosomes?

  • Chromosomal Duplication
  • Eukaryotic Overgrowth
  • Bacterial Infection
  • Down's Syndrome (correct)

    • Which statement is true regarding eukaryotic cells?

    <p>Their organelles perform specialized functions.</p> Signup and view all the answers

    Where is the DNA located in prokaryotic cells?

    <p>In a region known as the nucleoid</p> Signup and view all the answers

    What role does a cell nucleus play in eukaryotic cells?

    <p>It houses the cell's genetic information.</p> Signup and view all the answers

    How do the structures of prokaryotic and eukaryotic cells compare?

    <p>Eukaryotic cells are generally larger and more structurally complex.</p> Signup and view all the answers

    Which feature is common in all eukaryotic cells?

    <p>Presence of a nucleus</p> Signup and view all the answers

    What happens to homologous chromosomes during Anaphase I?

    <p>They are pulled towards opposite poles.</p> Signup and view all the answers

    Which of the following describes Telophase I?

    <p>Nuclear membranes may reform.</p> Signup and view all the answers

    What is a key feature of Meiosis II?

    <p>Sister chromatids are separated.</p> Signup and view all the answers

    What is the primary outcome of cytokinesis during Meiosis II?

    <p>Formation of four haploid cells.</p> Signup and view all the answers

    How many functional eggs are produced in females during meiosis?

    <p>One functional egg and three polar bodies.</p> Signup and view all the answers

    What does the term 'haploid' refer to in the context of meiosis?

    <p>Cells with one copy of each chromosome.</p> Signup and view all the answers

    What occurs during interphase before meiosis begins?

    <p>DNA replication and preparation for division.</p> Signup and view all the answers

    What role does genetic variability play in populations?

    <p>It enables change, adaptation, and evolution.</p> Signup and view all the answers

    What property of phospholipids allows them to form a bilayer in cell membranes?

    <p>Amphipathic nature</p> Signup and view all the answers

    How does cholesterol affect phospholipid movement at high temperatures?

    <p>Restricts movement of phospholipids</p> Signup and view all the answers

    What is the role of peripheral proteins in the cell membrane?

    <p>Do not penetrate the lipid bilayer</p> Signup and view all the answers

    What effect does cholesterol have on phospholipids at low temperatures?

    <p>Prevents close packing of phospholipids</p> Signup and view all the answers

    Which type of proteins span the entire phospholipid bilayer?

    <p>Integral proteins</p> Signup and view all the answers

    Which of the following movements of phospholipids occurs most frequently within the bilayer?

    <p>Lateral diffusion</p> Signup and view all the answers

    What are glycoproteins and glycolipids primarily responsible for?

    <p>Cell recognition and signaling</p> Signup and view all the answers

    What is the function of integral proteins in the phospholipid bilayer?

    <p>Facilitate transport across the membrane</p> Signup and view all the answers

    What term was coined by Waldeyer in 1888?

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

    What is the total number of chromosomes in humans?

    <p>46</p> Signup and view all the answers

    Which of the following best describes the role of histones in chromosomes?

    <p>They provide structural support for DNA packaging.</p> Signup and view all the answers

    What is the function of the centromere in chromosomes?

    <p>It serves as an attachment site for spindle fibers.</p> Signup and view all the answers

    What is the name of the specialized cell division that results in the production of gametes?

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

    Which of the following statements about extreme pH levels is TRUE?

    <p>They can inhibit cell division.</p> Signup and view all the answers

    In which phase of meiosis is the reduction of chromosome number achieved?

    <p>Meiosis I</p> Signup and view all the answers

    Which organisms are mentioned as having an impact on the rate of mitosis in plants?

    <p>Fungi and roundworms</p> Signup and view all the answers

    What is the primary requirement for active transport to occur?

    <p>Movement of molecules from low to high concentration</p> Signup and view all the answers

    Which process enables the cell to take in large solid objects?

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

    What is phagocytosis commonly referred to as?

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

    Which of the following describes the role of exocytosis?

    <p>Release of cellular waste</p> Signup and view all the answers

    What is the significance of the cell membrane's dynamic nature?

    <p>It can change in response to the cell's needs</p> Signup and view all the answers

    What represents the primary function of pinocytosis?

    <p>Intake of extracellular fluid</p> Signup and view all the answers

    Which molecule is primarily used for energy in active transport?

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

    What occurs during the process of endocytosis?

    <p>The cell membrane invaginates to engulf external substances</p> Signup and view all the answers

    Study Notes

    Cell Classification

    • All cells on Earth are categorized into prokaryotic and eukaryotic cells.
    • Prokaryotic cells lack a membrane-bound nucleus and organelles, with DNA located in the cytoplasm within a nucleoid region.

    Eukaryotic Cells

    • Eukaryotic cells have a well-defined nucleus and membrane-bound organelles, which contribute to their complex structure and functions.
    • A typical human cell contains 46 chromosomes, while individuals with Down's Syndrome may have 47 chromosomes.

    Chromosomes

    • Chromosomes are composed of DNA tightly packed with histones, which provide structural support.
    • The term "chromosome" was coined by Waldeyer in 1888; chromosomes were first identified by Strasburger in 1815.

    Meiosis Overview

    • Meiosis produces gametes (haploid cells) and consists of two stages: Meiosis I and Meiosis II.
    • Meiosis I is known as Reductional Division, where homologous chromosomes are separated, resulting in two haploid daughter cells.

    Meiosis Stages

    • Anaphase I: Homologous chromosomes are pulled to opposite poles.
    • Telophase I: Separated chromosomes reach opposite poles; nuclear membrane may reform.
    • Anaphase II: Sister chromatids are separated.
    • Telophase II: Nuclear membranes form around chromosomes, leading to the formation of four haploid cells.

    Cell Membrane Structure

    • Phospholipids, with hydrophilic heads and hydrophobic tails, are key components of the phospholipid bilayer.
    • Cholesterol within the membrane modulates fluidity; it decreases fluidity at high temperatures and increases it at low temperatures.

    Membrane Proteins

    • Peripheral Proteins: Located on the membrane surface and do not penetrate the lipid bilayer.
    • Integral Proteins: Span the membrane, functioning as carrier or channel proteins for transport.

    Transport Mechanisms

    • Active Transport: Moves substances from low to high concentration, requiring energy (ATP).
    • Endocytosis: The process where large substances enter the cell; involves invagination of the cell membrane to form an endocytic vesicle.
      • Phagocytosis: Engulfs large solid objects ("cell eating").
      • Pinocytosis: Takes in extracellular fluid ("cell drinking").

    Homeostasis and Cellular Dynamics

    • Cellular transport is crucial for maintaining homeostasis and involves active mechanisms for nutrient uptake and waste excretion.
    • The cell membrane is dynamic, capable of changing shape and composition to meet cellular needs, critical for communication and transport functions.

    Studying That Suits You

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

    Quiz Team

    Description

    This quiz covers essential concepts of cell classification, focusing on prokaryotic and eukaryotic cells. It explores the structural differences between these cells, the nature of chromosomes, and the process of meiosis. Perfect for students wanting to understand fundamental biology concepts.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser