Cell Biology and Microscopy Quiz

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the purpose of using a fixative like glutaraldehyde on tissue samples?

To preserve the cells within the tissue (correct)

To make the samples more opaque

To dissolve the tissue for easier examination

To enhance the color of the tissue samples

What is fluorescence microscopy primarily used for?

To observe cellular movement in real-time

To analyze the genetic material in cells

To create three-dimensional images of tissues

To detect specific proteins or other molecules (correct)

How does a confocal microscope differ from a conventional light microscope?

It focuses light on a single point at specific depths (correct)

It cannot produce three-dimensional images

It requires special staining techniques

It uses multiple light sources

What is the role of the filters in a fluorescence microscope?

To filter specific wavelengths of light Signup and view all the answers

What is the typical resolution limit of an electron microscope?

0.002 nm Signup and view all the answers

What happens to the wavelength of an electron as its velocity increases?

It decreases Signup and view all the answers

Why are tissue samples often cut into thin sections?

To facilitate high-resolution examination Signup and view all the answers

In fluorescence microscopy, what does the first filter do?

It passes only the wavelengths that excite the specific dye Signup and view all the answers

What type of bonds holds the two strands of DNA together?

Hydrogen bonds Signup and view all the answers

Which term describes a DNA fragment coding for a protein or non-coding RNA?

Gene Signup and view all the answers

What is the first process that utilizes DNA to synthesize RNA?

Transcription Signup and view all the answers

What structure encloses each cell and acts as a selective barrier?

Plasma membrane Signup and view all the answers

What are the molecules that make up the bilayer of the plasma membrane?

Phospholipids Signup and view all the answers

What process involves the synthesis of proteins directed by mRNAs?

Translation Signup and view all the answers

Which of the following domains of life has a nucleus?

Eukaryotes Signup and view all the answers

What can mutations lead to during DNA replication?

Genetic diversity Signup and view all the answers

What is the layer formed by amphiphilic components in water?

Bilayer Signup and view all the answers

Which structure is NOT found in prokaryotes?

Nucleus Signup and view all the answers

What is the primary purpose of the filament in the electron microscope?

To emit electrons Signup and view all the answers

Why must the air be pumped out of the column in the electron microscope?

To create a vacuum for the electron beam Signup and view all the answers

What is the usual thickness of the ultrathin sections of fixed tissue viewed in an electron microscope?

25–100 nm thick Signup and view all the answers

What role do the magnetic coils play in the operation of the electron microscope?

They focus the electron beam Signup and view all the answers

What process is often used to preserve living tissue before examining it with an electron microscope?

Chemical fixation Signup and view all the answers

What must be done to the specimen before it can be viewed in the electron microscope?

It must be cut into thin sections Signup and view all the answers

What kind of knife is used to cut the specimens in an electron microscope?

A fine glass or diamond knife Signup and view all the answers

What happens to living tissue when it is exposed to the vacuum in an electron microscope?

It is killed and preserved by chemical fixation Signup and view all the answers

How is the specimen prepared after dehydration for the electron microscope?

It is permeated with a resin Signup and view all the answers

What is the purpose of the small metal grid mentioned in the context of an electron microscope?

To support the specimen during viewing Signup and view all the answers

What is the primary function of the regulatory DNA in an organism's genome?

To control gene expression Signup and view all the answers

Which of the following correctly describes bacteriophages?

They are types of viruses that infect bacteria Signup and view all the answers

What are the two main approaches to analyzing gene function?

Biochemistry and Genetics Signup and view all the answers

Which statement about model organisms is true?

They aid in analyzing gene function through simplified systems Signup and view all the answers

How do viruses typically replicate their genetic information?

By using enzymes found in the host cell Signup and view all the answers

What characterizes the genome of coronaviruses?

It consists of large single-stranded RNA molecules Signup and view all the answers

What is the primary component of the hereditary information stored in cells?

Double-stranded DNA Signup and view all the answers

Which part of a DNA monomer provides structural framework?

Phosphate group Signup and view all the answers

What is a notable feature of bacteria as model organisms?

They duplicate every 20 minutes under optimal conditions Signup and view all the answers

In what form do all cells on Earth store their hereditary information?

Double-strand molecules of DNA Signup and view all the answers

What is the role of enzymes in biological systems?

They serve as biological catalysts. Signup and view all the answers

Which of the following cellular components is primarily linked to intercellular communication?

Cell membranes Signup and view all the answers

Which process is involved in the synthesis of RNA from a DNA template?

Transcription Signup and view all the answers

What structural form do most living organisms primarily consist of?

Single cells Signup and view all the answers

What is necessary for the flow of genetic information to occur?

DNA and RNA Signup and view all the answers

Which nucleotide bases are found in DNA?

A, G, C, T Signup and view all the answers

Which polymerase is involved in the transcription process in eukaryotes?

RNA polymerase Signup and view all the answers

Study Notes

Course Information

Course: Biology and Genetics I
Academic Year: 2024-2025
Instructor: Prof. Cecilia Battistelli
Email: [email protected]

Course Content

Introduction to cellular biology: diversity and similarity of living organisms, Biology and the scientific method, Origin and Evolution of Cells, Cells as experimental models, Tools of Cell Biology, The Chemistry of Life (molecular composition of cells), Enzymes as biological catalysts
The flow of genetic information: Nucleic acids, Chromatin and Chromosomes, DNA Replication, DNA Repair, RNA Synthesis and Processing (transcription in prokaryotes, eukaryotic RNA polymerases, general transcription factors, regulation of transcription in eukaryotes, RNA processing and turnover), Protein Synthesis, Processing, and Regulation (translation of mRNA, protein folding and processing, regulation of protein function, protein degradation)
Human genetics and techniques

Recommended Texts

Cell and Molecular Biology (Gerald Karp, Wiley & Sons, Inc)
World of the Cell (Becker, Kleinsmith, Hardin, Bertoni, Pearson Education)
The Cell, a molecular approach (Geoffrey M Cooper, Sinauer)
Molecular Biology of the Cell (Bruce Alberts, NCBI bookshelf online)

Exam Information

Written test for both biology I and genetics I, on either 12/02/2025 or 26/2/2025
Registration via GOMP website

Lecture Schedule

Lectures from October 7, 2024 to January 30, 2025
Time: 14:00 to 16:00

Additional Topics (from subsequent pages)

Cells, Genomes, and the Diversity of Life
Most living organisms are single cells. Others form groups linked by intercellular communication, generated from a single cell.
All cells store hereditary information as double-stranded DNA. DNA strands consist of sugars, phosphates, and bases (A, T, C, G).
DNA replication uses one strand as a template for a complementary strand.
DNA expresses information by guiding the synthesis of other molecules (genes for proteins/non-coding RNA). RNA synthesis (transcription) followed by protein synthesis (translation).
Proteins act in various cellular functions, including catalysis(speeding up chemical reactions without changing themselves). They maintain hereditary information.
Cells have plasma membranes that act as selective barriers for molecules. Plasma membranes are formed of amphiphilic phospholipids.
All membranes contain membrane transport proteins.
Differences in DNA sequence provide quantitative measures of evolutionary distance. The living world encompasses three domains: Eukaryotes, Bacteria, and Archaea.
Eukaryotes have a nucleus, Bacteria and Archaea do not. Bacteria can be spherical, rod-shaped, or spiral.
Mutations occur during DNA replication and repair, including gene duplication, break and rejoin of DNA segments, and transfer of DNA between cells.
Genes derived from a common ancestor are orthologs; duplicated genes that diverge functionally are paralogs.
Many genes are common to all three domains of life, involved in roles such as information processing and metabolic activities.
Eukaryotic cells are complex, containing organelles and a cytoskeleton.
Eukaryotic cells may employ endocytosis (import) and exocytosis (export) to mediate material exchange between organelles.
Other organelles, like mitochondria and chloroplasts, are enclosed in a double membrane. Mitochondria produce ATP from food molecules. They are similar in structure to bacteria.
Eukaryotic cells evolved through endosymbiosis between an anaerobic archaeon and an aerobic bacterium.
Some prokaryotic genes transitioned to eukaryotic nuclei.
Eukaryotic DNA is large, with significant non-coding regions that control gene expression,
Model organisms are used in gene function analyses (combined biochemistry and genetics approaches, using mutants).
Viruses, including bacteriophages that infect bacteria, use diverse methods of gene transfer.
Bacteria can adapt to variable conditions via mutation and selection.
Yeast (a eukaryotic organism), are easy to grow in simple medium, capable of both sexual and asexual reproduction.
Variety of model organisms used in biological research and studies.
Visualizing Cells and Their Molecules (using light microscopy variations like brightfield, darkfield, phase-contrast, and electron microscopy—scanning/transmission)
Techniques to visualize cell structures include staining, sectioning (for thick samples), and using fluorescent dyes. Techniques to isolate and separate proteins include column chromatography, polyacrylamide-gel electrophoresis, and mass spectrometry.
Analysis of large, complex macromolecules like DNA and proteins relies on techniques like x-ray crystallography and cryo-electron microscopy.

Studying That Suits You

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

Description

Test your knowledge on the fundamentals of cell biology and various microscopy techniques. This quiz covers important concepts such as fixatives, fluorescence microscopy, electron microscopy, and the molecular structure of DNA. Get ready to dive into the microscopic world of cells and their components!