Genes & Health

• What increases the rate of gas exchange by diffusion?

  Increased surface area, decreased distance, steeper gradient
• What does Fick's Law state about diffusion?

  Larger area and concentration difference increase rate

  
• How are mammal lungs adapted for gas exchange?

  Large surface area, good blood supply, short distance
• Why is a good blood supply important for lungs?

  It maintains a steep concentration gradient
• What is the thickness of alveoli in mammal lungs?

  One cell thick
• What are the main components of a cell membrane?

  • Phospholipid bilayer
  • Proteins (transport, receptor, enzymes, structural, recognition)
• What is the main function of the cell membrane?

  Controls movement of substances in and out
• What model describes the structure of the cell membrane?

  Fluid mosaic model
• What factors affect the movement of molecules through the cell membrane?

  Properties of the molecule and cell requirements
• What are the types of movement through cell membranes?

  • Diffusion
  • Facilitated diffusion
  • Osmosis
  • Active transport
  • Endocytosis/Exocytosis
• What is diffusion?

  Passive movement of small, non-polar molecules
• What increases the rate of gas exchange by diffusion?

  Increased surface area, decreased distance, steeper gradient
• What is facilitated diffusion?

  Transport of polar molecules via channel proteins
• What is osmosis?

  Movement of water from low to high solute concentration
• What is active transport?

  Transport against concentration gradient using energy
• What is the role of ATP in active transport?

  Provides energy for transporting molecules
• What is endocytosis?

  Transport of large particles into the cell
• What is exocytosis?

  Transport of large particles out of the cell
• What are the components of a mononucleotide?

  • Bases: adenine, guanine, cytosine, thymine
  • Sugar: deoxyribose
  • Phosphate group

  
• What are the base pairing rules in DNA?

  A pairs with T, C pairs with G
• What type of bonds hold the DNA structure together?

  Hydrogen bonds and phosphodiester bonds
• What is the structure of DNA?

  Double-stranded alpha double helix
• What are the components of mRNA?

  • Bases: adenine, guanine, cytosine, uracil
  • Sugar: ribose
  • Structure: single-stranded
• What is the function of tRNA?

  Carries anticodons complementary to mRNA codons

  
• What are the stages of protein synthesis?

  1. Transcription in the nucleus
  2. Translation at the ribosomes
• What happens during transcription?

  DNA is transcribed into mRNA

  
• What is the role of RNA polymerase in transcription?

  Catalyzes the formation of mRNA
• What occurs during translation?

  Amino acids join to form a polypeptide chain
• What is a gene?

  A series of bases coding for amino acids
• What is the genetic code?

  Order of bases coding for amino acids
• What is the significance of triplets in the genetic code?

  Each triplet codes for a specific amino acid
• What happens to amino acids during protein synthesis?

  They are joined by peptide bonds to form chains
• What is the role of non-coding sections of DNA?

  Not all genome codes for proteins
• What is the role of mechanical ventilation in maintaining concentration gradients in lungs?

  It ensures high oxygen and low carbon dioxide levels
• What is the process of phosphorylation of ATP?

  It requires energy to add a phosphate group
• What are the specific functions of different types of membrane proteins?

  Transport, receptor, enzyme, structural, recognition
• What is the significance of the sugar-phosphate backbone in nucleic acids?

  It provides structural support to the DNA/RNA

  
• What are the differences between DNA and RNA structures?

  DNA is double-stranded; RNA is single-stranded
• What is the importance of the ribosome in translation?

  It joins amino acids to form polypeptide chains
• What is a codon?

  A triplet of bases coding for an amino acid