Tissue Fixation in Biology
52 Questions
2 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 primary objective of tissue fixation?

  • To preserve the chemical composition of the sample
  • To preserve the cells and tissue components as close to normal as possible (correct)
  • To increase the mechanical strength of the sample
  • To prevent extrinsic damage to the sample

    • How does fixative typically protect a sample from damage?

  • By altering the cells or tissues on a molecular level
  • By killing any microorganisms that may be present in the sample
  • By increasing the mechanical stability of the sample
  • By disabling intrinsic biomolecules that would otherwise damage the sample (correct)

    • What is the purpose of the additional processing steps and final analyses that are planned?

  • To further preserve the morphology of the sample
  • To increase the mechanical strength of the sample
  • To chemically mask the protein targets for immunohistochemistry
  • To determine the appropriate fixation method to use (correct)

    • How does heat fixation differ from other fixation methods?

    <p>It preserves overall morphology but not internal structures</p> Signup and view all the answers

    What is the effect of prolonged fixation on immunohistochemistry analysis?

    <p>It chemically masks the protein targets, preventing antibody binding</p> Signup and view all the answers

    What is the purpose of mixing the sample with water or physiological saline in heat fixation?

    <p>To evenly spread out the sample for fixation</p> Signup and view all the answers

    Which of the following is the most common staining technique used in routine histological analysis?

    <p>Hematoxylin and eosin (H&amp;E) stain</p> Signup and view all the answers

    What is the primary function of the counterstain in a staining procedure?

    <p>To differentiate between different cellular structures</p> Signup and view all the answers

    Which of the following is a characteristic of the Leishman stain?

    <p>It stains the nuclei blue and the cytoplasm pink</p> Signup and view all the answers

    What is the primary purpose of staining biological tissues for microscopic examination?

    <p>To highlight specific cellular components or structures</p> Signup and view all the answers

    Which of the following factors can influence the intensity of staining in a tissue section?

    <p>The concentration of the target tissue</p> Signup and view all the answers

    Which of the following is a characteristic of an artifact in a microscopic tissue preparation?

    <p>It is a distortion or alteration caused by the preparation process</p> Signup and view all the answers

    Which of the following is a primary component of the Leishman stain?

    <p>Methylene blue</p> Signup and view all the answers

    What is the primary function of the fixative used in tissue preparation?

    <p>To preserve the morphological structure of the tissue</p> Signup and view all the answers

    Which of the following is a characteristic of natural dyes used in tissue staining?

    <p>They are rarely used in modern histological techniques</p> Signup and view all the answers

    What is the primary purpose of using a counterstain in a tissue preparation?

    <p>To differentiate between different cellular structures</p> Signup and view all the answers

    What is the primary purpose of the fixation process in tissue preparation?

    <p>To stabilize the proteins, nucleic acids, and microsubstances of the tissue in a state as close to living tissue as possible</p> Signup and view all the answers

    Which factor is least important in determining the effectiveness of chemical fixation?

    <p>The type of microscopy technique to be used for analysis</p> Signup and view all the answers

    What is the purpose of the clearing step in tissue processing?

    <p>To replace the ethanol in the tissue sample with an organic solvent miscible with both alcohol and the embedding medium</p> Signup and view all the answers

    Which of the following statements is true regarding the embedding process in tissue preparation?

    <p>The embedding medium provides support and prevents distortion of the tissue during sectioning</p> Signup and view all the answers

    What is the typical thickness range of tissue sections cut for transmission electron microscopy?

    <p>0.1-0.5 micrometers (µm)</p> Signup and view all the answers

    Which of the following statements is true regarding the mounting of tissue sections?

    <p>Sections are floated in a water bath before being mounted onto glass slides</p> Signup and view all the answers

    What is the primary advantage of using the freezing method for tissue fixation?

    <p>It provides rapid fixation results</p> Signup and view all the answers

    Which of the following statements is true regarding the duration of chemical fixation?

    <p>A general rule is to allow 1 hour of fixation per 1 millimeter of tissue thickness</p> Signup and view all the answers

    What is the purpose of the dehydration step in tissue processing?

    <p>To remove water from the tissue and replace it with a series of increasingly concentrated alcohol solutions</p> Signup and view all the answers

    Which of the following factors should be considered when selecting the embedding medium for tissue preparation?

    <p>The type of tissue and the intended microscopy technique</p> Signup and view all the answers

    Fixation is the final step in the process to prepare a sample of biological material for microscopy analysis.

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

    Fixatives are non-toxic to common microorganisms like bacteria.

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

    The purpose of fixation is solely to increase the mechanical strength of cells and tissues.

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

    Heat fixation is commonly used for multicellular organisms like plants.

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

    Quick fix using cold formalin for around 24 hours is primarily used in immunohistochemistry to enhance antibody binding.

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

    Fixatives do not alter cells or tissues at a molecular level.

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

    Leishman stain is mainly used for staining DNA in the cell nucleus.

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

    Acidic dyes bind with negatively charged basophilic tissue.

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

    Hematoxylin stains RNA-rich portions of the cytoplasm pink.

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

    The nuclei take up a pink stain with Leishman stain.

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

    Eosin is considered a primary dye in H&E staining.

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

    Neutral dyes are commonly extracted from plants and animals.

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

    Chelating dyes are used based on tissue geometry.

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

    Artifacts can occur due to extraneous factors before fixation only.

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

    Natural dyes are mostly petroleum derivatives.

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

    Heat fixation is typically used in routine histological analysis.

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

    In tissue processing, dehydration removes all water from the tissue by using diluted alcohol solutions.

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

    The pH for ultrastructure preservation during fixation should be buffered between 7.2 to 7.4.

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

    Hypertonic fixatives result in cell swelling and poor fixation.

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

    Embedding for electron microscopy commonly uses paraffin wax as the embedding medium.

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

    The thickness of tissue sections cut for light microscopy using a steel knife is typically 5-10 µm.

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

    Tissue freezing is a method that provides fine details but does not give rapid results.

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

    An ideal thickness for tissue specimens during fixation is between 1-4 cm.

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

    Embedding for electron microscopy involves using molds to harden the tissue samples.

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

    Chemical fixation occurs within milliseconds and allows preservation of structures in their native state.

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

    FFPE tissues can only be stored at low temperatures to prevent degradation.

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

    More Like This

    Fixatives for Nervous Tissue
    40 questions

    Fixatives for Nervous Tissue

    AwestruckWalrus avatar
    AwestruckWalrus
    Biological Fixation and Its Functions
    10 questions

    Biological Fixation and Its Functions

    LikedJudgment7520 avatar
    LikedJudgment7520
    Types of Microscopes and Tissue Sampling
    22 questions

    Types of Microscopes and Tissue Sampling

    FearlessEuropium avatar
    FearlessEuropium
    Microscopie en Weefselfixatie Quiz
    48 questions

    Microscopie en Weefselfixatie Quiz

    SuccessfulPelican avatar
    SuccessfulPelican
    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser