Chapter 1

• What are the two main types of cells that all living things are made of?


  Prokaryotic and eukaryotic cells
• What type of cells are animal and plant cells classified as?

  They are classified as eukaryotic cells
• What are the main components of eukaryotic cells?

  • Cell membrane
  • Cytoplasm
  • Nucleus containing DNA
• What distinguishes bacterial cells from eukaryotic cells?

  Bacterial cells are prokaryotic and much smaller
• What are the main components of prokaryotic cells?

  • Cell wall
  • Cell membrane
  • Cytoplasm
  • Single circular strand of DNA
  • Plasmids (small rings of DNA)
• What are organelles in a cell?

  Organelles are structures in a cell that have different functions
• What does it mean if an object is 1000 times bigger than another?

  It is said to be 10³ times bigger
• How do we express that an object is 10 times smaller than another?

  It is said to be 10¹ times smaller
• What are the prefixes used to denote multiples of units of measurement?

  • Centi: Multiply unit by 0.01
  • Milli: Multiply unit by 0.001
  • Micro: Multiply unit by 0.000001
  • Nano: Multiply unit by 0.000000001
• What is therapeutic cloning?

  Therapeutic cloning involves producing an embryo with the same genes as the patient.
• What can be harvested from the embryo produced in therapeutic cloning?

  Embryonic stem cells can be harvested from the embryo.
• How can embryonic stem cells be utilized for a patient?

  They can be grown into any cells the patient needs, such as new tissues or organs.
• Why would stem cells from therapeutic cloning not be rejected by the patient?

  They would not be rejected because they have the exact same genetic make-up as the individual.
• What are the benefits and problems of research with stem cells?

  Benefits:

  • Can replace damaged or diseased body parts.
  • Unwanted embryos from fertility clinics could be used.

  
  

  Problems:

  • Lack of understanding of differentiation makes control difficult.
  • Removal of stem cells results in destruction of the embryo.
  • Ethical objections regarding interference with reproduction.
  • Risk of viral contamination from growing stem cells.
  • Resources could be better spent in other medical areas.
• What is the definition of diffusion?

  Diffusion is the spreading out of particles resulting in a net movement from higher to lower concentration.
• Why does diffusion occur more frequently when particles are close together?

  Particles collide with each other more often when they are close together, leading to mixing.
• Is diffusion an active or passive process?

  Diffusion is a passive process as it does not require energy.
• What types of molecules can move across cell membranes via diffusion?

  Small molecules such as oxygen, glucose, amino acids, and water can move across cell membranes.
• Which molecules cannot move across cell membranes via diffusion?

  Starch and proteins cannot move across cell membranes via diffusion.
• Where does diffusion take place in the body?

  • In the lungs for gas exchange (oxygen and carbon dioxide).
  • In the intestines for nutrient absorption.
  • In the kidneys for waste removal.
• Scientists use their knowledge and experience to formulate hypotheses, which are educated guesses based on previous research and observations.