Topic 2: BIO

• What is the overall function of the nucleus in eukaryotic cells?

  DNA replication and transcription of mRNA
• What are the key structures within the nucleus?

  Nuclear envelope, nuclear pores, nucleoplasm, chromosomes, and nucleolus
• What is the role of the nucleolus?

  Site of RNA production and ribosome assembly
• What distinguishes rough endoplasmic reticulum (RER) from smooth endoplasmic reticulum (SER)?

  The presence of ribosomes on the RER
• What is the primary function of the rough endoplasmic reticulum?

  Protein synthesis
• What is the primary function of the smooth endoplasmic reticulum?

  Synthesis and storage of lipids and carbohydrates
• What is the structure of the Golgi apparatus?

  A folded membrane system with vesicles pinching off
• What types of molecules can the Golgi apparatus modify?

  Carbohydrates, proteins, and lipids
• What are lysosomes and their primary function?

  Bags of digestive enzymes involved in hydrolysis
• What is the role of mitochondria in cells?

  Site of aerobic respiration and ATP production
• What is the structure of ribosomes?

  Made up of rRNA and proteins
• What is the difference in ribosome size between eukaryotic and prokaryotic cells?

  Eukaryotic cells have 80S ribosomes, while prokaryotic cells have 70S ribosomes
• What is the function of vacuoles in plant cells?

  To provide turgidity and store substances
• What is the role of chloroplasts in plant cells?

  Site of photosynthesis
• What are thylakoid membranes and their function?

  Membranes that contain chlorophyll and are involved in light-dependent reactions
• What is the function of the cell wall in plant and fungal cells?

  To provide structural strength and prevent bursting
• What is the composition of the plasma membrane?

  Phospholipid bilayer with embedded molecules
• What are the key differences between prokaryotic and eukaryotic cells?

  Prokaryotic cells are smaller, lack membrane-bound organelles, and have a single loop of DNA
• What is the structure of viruses?

  Consists of genetic material, capsid, and attachment proteins
• Why is it difficult to destroy viruses?

  Because they replicate inside host cells
• What are the methods of studying cells mentioned in the material?

  Microscopy, cell fractionation, and ultracentrifugation
• What is the definition of magnification?

  How many times larger the image is compared to the object
• What determines the resolution of an optical microscope?

  The wavelength of light
• What is the difference in resolution between optical and electron microscopes?

  Electron microscopes have a higher resolution due to shorter wavelengths
• What is the advantage of optical microscopes over electron microscopes?

  They can view living samples and produce color images
• What is the difference between transmission and scanning electron microscopes?

  Transmission electron microscopes produce 2D images, while scanning electron microscopes produce 3D images
• What is the formula for calculating magnification?

  Image size = Actual size × Magnification
• What conditions must be met for cell fractionation?

  Cold, isotonic, and buffered solution
• What is the first step in cell fractionation?

  Homogenization to break open the cells
• What is differential centrifugation?

  A process that separates organelles based on their densities
• What is the order of density for organelles during centrifugation?

  Nuclei, chloroplasts, mitochondria, lysosomes, endoplasmic reticulum, ribosomes
• What are the key stages of the eukaryotic cell cycle?

  Interphase, mitosis, and cytokinesis
• What happens during the S phase of interphase?

  DNA replication occurs
• What is the final stage of the cell cycle?

  Cytokinesis
• What are the four key stages of mitosis?

  Prophase, metaphase, anaphase, and telophase
• What type of cells are produced by mitosis?

  Genetically identical diploid cells
• How do prokaryotic cells replicate?

  By binary fission
• How do viruses replicate?

  Inside a host cell by injecting their nucleic acid
• What is the role of the host cell in viral replication?

  To use the viral genetic material to replicate the virus particle
• What happens during the G1 phase of interphase?

  The cell increases in size and organelles double