Topic 2 bio

• What are the key organelles in eukaryotic cells?

  • Nucleus
  • Endoplasmic reticulum (smooth and rough)
  • Golgi apparatus
  • Lysosomes
  • Mitochondria
  • Ribosomes
  • Vacuole
  • Chloroplasts
  • Cell wall
  • Plasma membrane
• What is the function of the nucleus?

  DNA replication and transcription
• What is produced in the nucleolus?

  Ribosomes
• What distinguishes rough endoplasmic reticulum from smooth endoplasmic reticulum?

  Rough ER has ribosomes on its surface
• What is the function of the rough endoplasmic reticulum?

  Protein synthesis
• What does the smooth endoplasmic reticulum synthesize?

  Lipids and carbohydrates
• What is the structure of the Golgi apparatus?

  Folded membrane system
• What happens to molecules in the Golgi apparatus?

  They are modified and packaged
• What are lysosomes filled with?

  Digestive enzymes
• What is the function of lysosomes?

  Involved in phagocytosis
• What is the primary function of mitochondria?

  Aerobic respiration and ATP production
• What type of DNA do mitochondria have?

  Loop of DNA similar to prokaryotic
• What are ribosomes made of?

  rRNA and proteins
• What size ribosomes are found in eukaryotic cells?

  80S
• What is the function of vacuoles in plant cells?

  Provide support and store substances
• What is the function of chloroplasts?

  Site of photosynthesis
• What are thylakoid membranes involved in?

  Light-dependent reactions of photosynthesis
• What is the function of the cell wall?

  Provide structural strength
• What is the composition of plant cell walls?

  Cellulose
• What is the role of the plasma membrane?

  Controls entry and exit of substances
• What is a key difference between prokaryotic and eukaryotic cells?

  Prokaryotic cells lack membrane-bound organelles
• What is the structure of prokaryotic DNA?

  Single loop free in cytoplasm
• What is the function of plasmids in prokaryotic cells?

  Additional loops of DNA
• What are viruses classified as?

  Acellular and non-living
• What is the structure of a virus particle?

  Genetic material, capsid, and proteins
• How do viruses replicate?

  Inside host cells by injecting nucleic acid
• What are the methods of studying cells?

  1. Microscopy

  • Optical microscopes
  • Electron microscopes (TEM and SEM)

  1. Cell fractionation
  2. Ultra centrifugation
• What is the definition of magnification?

  How many times larger the image is
• What determines the resolution of optical microscopes?

  Wavelength of light
• What is the advantage of electron microscopes over optical microscopes?

  Higher resolution due to shorter wavelength
• What is the difference between transmission and scanning electron microscopes?

  TEM produces 2D images, SEM produces 3D images
• What is the formula for calculating magnification?

  Image size = actual size × magnification
• Why must the eyepiece graticule be recalibrated?

  Each time the objective lens changes
• What are the conditions for cell fractionation?

  Cold, isotonic, and buffered solution
• What is homogenization in cell fractionation?

  Breaking open cells to release contents
• What is the order of density in organelles during centrifugation?

  Nuclei, chloroplasts, mitochondria, lysosomes, ER, ribosomes
• What is the cell cycle in eukaryotic cells?

  Includes interphase, mitosis, and cytokinesis
• What happens during the G1 phase of interphase?

  Cell increases in size and doubles organelles
• What is the purpose of the G2 phase in interphase?

  Preparation for mitosis and error checking
• What are the stages of mitosis?

  Prophase, metaphase, anaphase, telophase