Cells & Microscopy

• What is the fundamental building block of life according to cell theory?

  Cells
• What does the cell theory state about living organisms?

  All living organisms are composed of one or more cells.
• What is the basic unit of structure, function, and organization in all organisms?

  The cell
• From where do all cells originate according to cell theory?

  All cells come from pre-existing cells.
• What are cells enclosed by?

  A cell membrane
• What do organelles within cells do?

  Each organelle has specific functions necessary for life.
• What do all living organisms, from bacteria to animals, consist of?

  Cells
• What does the universality of cells suggest?

  It suggests a common origin for all life on Earth.
• What are the two main types of cells?

  • Prokaryotic cells: Simpler, lack a nucleus.
  • Eukaryotic cells: More complex, have membrane-bound organelles.
• What is a characteristic of prokaryotic cells?

  They lack a nucleus.
• What is a characteristic of eukaryotic cells?

  They have membrane-bound organelles.
• What are the steps involved in the development of cell theory?

  1. Observations using microscopes
  2. Hypothesis formation
  3. Experimentation
  4. Deductive reasoning
• What are the common structures found in all living cells?

  • DNA: Hereditary material
  • Cytoplasm: Medium for reactions
  • Plasma Membrane: Cell boundary
• What is the function of DNA in cells?

  It stores genetic information.
• Why is cytoplasm important in cells?

  It provides a medium for cellular reactions.
• What is the water content of cytoplasm, and why is it important?

  About 70-90%, crucial for biochemical reactions.
• What is the function of the plasma membrane?

  It controls what enters and exits the cell.
• Why is the lipid bilayer structure of the plasma membrane crucial?

  It allows selective permeability and maintains cell integrity.
• What is the composition of the cell wall in Gram-positive bacteria?

  Thick peptidoglycan.
• What is the function of the cell wall in Gram-positive bacteria?

  It provides structural support and maintains cell shape.
• What is the function of the plasma membrane in prokaryotic cells?

  It controls movement of substances in and out of the cell.
• What type of DNA do prokaryotes have?

  Naked DNA in a loop.
• What are 70S ribosomes and their function?

  They are smaller ribosomes in prokaryotes, serving as the site of protein synthesis.
• What are additional structures found in prokaryotic cells?

  • Pili: For attachment or DNA transfer.
  • Flagella: For movement.
  • Capsule: Extra layer outside the cell wall.
• How does prokaryotic cell structure vary?

  Some lack cell walls, and Gram-negative bacteria have a thinner peptidoglycan layer.
• What is the function of the plasma membrane in eukaryotic cells?

  It controls movement of substances and is involved in cell signaling.
• What is the function of compartmentalized cytoplasm in eukaryotic cells?

  • Provides a medium for cellular reactions.
  • Houses organelles and cytoskeleton.
• What are 80S ribosomes and their function?

  They are larger ribosomes in eukaryotes, serving as the site of protein synthesis.
• What are the components of the nucleus?

  • Chromosomes: DNA bound to histones.
  • Nuclear envelope: Double membrane with pores.
  • Nucleolus: Site of ribosome production.
• What is the function of the nucleus?

  It houses and protects genetic material and controls gene expression.
• What are the functions of membrane-bound organelles?

  • Mitochondria: Energy production.
  • Endoplasmic Reticulum (ER): Protein and lipid synthesis.
  • Golgi Apparatus: Modification and distribution of proteins.
  • Vesicles and Vacuoles: Storage, transport, digestion.
• What is the function of mitochondria?

  Energy production through cellular respiration.
• What is the function of the cytoskeleton?

  It maintains cell shape and facilitates movement within the cell.
• What are the key cellular processes?

  1. Cellular Respiration
  2. Protein Synthesis
  3. Cell Division
  4. Cell Signaling
• What is cellular respiration?

  A metabolic process that converts nutrients into ATP and releases waste products.
• What is the general equation for cellular respiration?

  $\text{C}_6\text{H}_{12}\text{O}_6 +$$6\text{O}_2 \rightarrow 6\text{CO}_2 +$$6\text{H}_2\text{O} +$$\text{ATP}$
• Why is ATP important for cells?

  It serves as the energy currency of the cell.
• What is protein synthesis?

  The process by which cells generate new proteins essential for various functions.
• What are the stages of protein synthesis?

  1. Transcription: DNA is copied into mRNA.
  2. Translation: mRNA is translated into a polypeptide chain at the ribosome.
• What are the key components involved in protein synthesis?

  Ribosomes, mRNA, and tRNA.