Biological molecules

• What is the structure of DNA in eukaryotic cells?


  DNA is organized into linear chromosomes.
• What happens to chromatin when cells are not dividing?


  Chromatin is spread out.
• What is the function of ribosomes in eukaryotic cells?


  Ribosomes assemble proteins.
• What are the main functions of the endoplasmic reticulum (ER)?


  • Transports substances within the cell
  • Assembles proteins
  • Has a large surface area for ribosomes
• What is the role of the Golgi apparatus?


  The Golgi apparatus modifies proteins.
• What is the function of lysosomes?


  Lysosomes contain enzymes that catalyze reactions involved in lipid metabolism.
• What is the primary function of mitochondria?


  Mitochondria are the site of ATP production.
• What is the structure of the chloroplast?


  Chloroplasts are surrounded by a double membrane and contain thylakoids.
• What is the function of vacuoles in plant cells?


  Vacuoles store water in plant cells.
• What are the main components of the cytoskeleton?


  • Microfilaments (actin)
  • Intermediate filaments (tubulin)
  • Microtubules
• What is the role of centrioles in eukaryotic cells?


  Centrioles are involved in the formation of cilia and undulipodia.
• What is the difference between prokaryotic and eukaryotic cells regarding organelles?


  Prokaryotic cells do not have membrane-bound organelles.
• What are the similarities and differences between prokaryotic and eukaryotic cells?


  Similarities:

  • Have plasma membrane
  • Have cytoplasm
  • Have ribosomes
  • Have DNA and RNA

  
  

  Differences:

  • Prokaryotic cells are smaller and less developed
  • Prokaryotic cells lack a nucleus and membrane-bound organelles
• What is the function of plasmids in prokaryotic cells?


  Plasmids are small loops of DNA.
• What is the process of transcription?


  Transcription is the process of making a copy of DNA in the form of mRNA.
• What is the role of insulin in the body?


  Insulin reduces blood glucose levels when they get too high.
• What is the endosymbiont theory?


  The endosymbiont theory suggests that eukaryotic cells evolved from prokaryotes.
• What is the resolution limit of light microscopes?


  The resolution limit of light microscopes ranges from 400 to 700 nm.
• How do organelles work together to make and secrete a protein?


  1. Gene coding for protein is transcribed into mRNA in the nucleus.
  2. mRNA exits the nuclear envelope.
  3. Ribosomes translate mRNA into proteins.
  4. Proteins are assembled and pass into the RER.
  5. Vesicles transport proteins to the Golgi apparatus for modification.
  6. Modified proteins are released via exocytosis.
• What is the process of translation?


  Translation is the process where mRNA is used to make a polypeptide.
• What is a polypeptide?


  A polypeptide is a long string of amino acids.
• How do prokaryotic cells divide?


  Prokaryotic cells divide by binary fission.
• What is the significance of the three domains of life?


  The three domains indicate the evolutionary relationships among organisms.
• What is the function of the cell wall in plant cells?


  The cell wall provides strength and support to maintain cell shape.
• What is the role of ribosomes on the rough endoplasmic reticulum (RER)?


  Ribosomes on the RER make proteins to be secreted.
• What is the diameter of microfilaments?


  Microfilaments are about 7 nm in diameter.
• What is the diameter of microtubules?


  Microtubules are 18-30 nm in diameter.
• What is the function of motor proteins in the cytoskeleton?


  Motor proteins walk along the cytoskeleton using ATP.
• What is the role of the nucleolus?


  The nucleolus is where ribosomes are made.
• What is the role of chlorophyll in chloroplasts?


  Chlorophyll is involved in photosynthesis.
• What is the function of the cytoplasmic matrix?


  The cytoplasmic matrix is filled with fluid and supports organelles.
• What is the significance of the Golgi apparatus in protein secretion?


  The Golgi apparatus modifies and packages proteins for secretion.
• What is the primary component of the cell wall in plant cells?

  The primary component of the cell wall in plant cells is cellulose.
• What is the role of the plasma membrane?


  The plasma membrane controls what substances enter and exit the cell.
• What is the diameter of intermediate filaments?


  Intermediate filaments are about 10 nm in diameter.
• What is the function of the cell membrane?

  The cell membrane is involved in metabolic activity and controls substance movement.
• What is the function of the rough endoplasmic reticulum (RER)?


  The RER is involved in protein synthesis.
• What is the role of the cytoskeleton in the cell?


  The cytoskeleton provides structure and support to the cell.
• What is the function of the smooth endoplasmic reticulum (SER)?


  The SER is involved in lipid metabolism and detoxification.
• What is the significance of the cell theory?


  The cell theory states that all living organisms are composed of cells.