things i dont get

• What is the definition of osmosis?


  Osmosis is the movement of water molecules from an area of high water concentration to an area of low water concentration across a semi-permeable membrane.
• What are the key points of osmosis?


  • Involves water molecules
  • Moves from high to low concentration
  • Occurs across a semi-permeable membrane
  • Passive process (no energy required)
• How can osmosis be simplified for better understanding?


  Osmosis is like water trying to balance itself out by moving to the side with more dissolved stuff.
• In osmosis, if one container has pure water and the other has salt water, where will the water move?


  Water will move from the pure water to the salt water.
• What is a concentration gradient?


  A concentration gradient is the difference in the concentration of a substance between two areas.
• If Solution A has a 10% sugar concentration and Solution B has a 20% sugar concentration, which has a higher water concentration?


  Solution A (10% sugar) has a higher water concentration.
• What is the role of semi-permeable membranes in osmosis?


  • Selectively permeable: allows some substances through, not others
  • Usually allows small molecules like water to pass
  • Often blocks larger molecules like proteins or ions
  • In cells, the cell membrane acts as a semi-permeable membrane
• What happens when a bag made of dialysis tubing containing glucose solution is placed in pure water?


  The bag will increase in size as water moves into it.
• What do the terms hypotonic, hypertonic, and isotonic mean?

  • Hypotonic: Lower solute concentration compared to another solution
  • Hypertonic: Higher solute concentration compared to another solution
  • Isotonic: Equal solute concentrations in two solutions
• What happens to a cell in a hypotonic solution?


  The cell will gain water and may swell or burst.
• What happens to a cell in a hypertonic solution?


  The cell will lose water and shrink.
• What happens to a cell in an isotonic solution?


  The cell maintains its normal size with no net movement of water.
• What is likely to happen to a plant cell placed in a concentrated sugar solution?

  The cell will undergo plasmolysis, with the cell membrane pulling away from the cell wall.
• What is the definition of osmosis?


  Osmosis is the movement of water molecules from an area of high water concentration to an area of low water concentration across a semi-permeable membrane.
• What type of transport is osmosis classified as?


  Osmosis is classified as passive transport.
• What drives the process of osmosis?


  The concentration gradient of water drives the process of osmosis.
• What does a semi-permeable membrane allow to pass through?


  A semi-permeable membrane allows water to pass but not larger molecules.
• What happens when a bag of sugar is placed in water in terms of osmosis?


  Water molecules will move into the bag, diluting the sugar solution.
• How can osmosis be explained in simpler terms?


  • Water molecules move to areas with less water.
  • They pass through special doors (semi-permeable membrane).
  • They do not need energy to move.
• What is the role of the cell membrane in plant cells regarding osmosis?


  The cell membrane controls what enters and exits the cell, including water during osmosis.
• What happens to a plant cell when it is placed in pure water?

  Water moves into the cell, causing the vacuole to expand and the cell to become turgid.
• What is the effect of a hypertonic solution on a plant cell?


  Water moves out of the cell, causing the cell to become plasmolyzed (shrunken).
• What is turgor pressure in plant cells?


  Turgor pressure is the internal pressure that helps maintain cell shape and plant rigidity.
• What happens to plant cells in a hypotonic solution?


  Plant cells become turgid as water moves into the cell.
• What is the outcome when a plant cell is placed in an isotonic solution?


  There is no net movement of water, and the cell remains normal.
• How does osmosis contribute to nutrient transport in plants?


  Osmosis assists in moving dissolved nutrients throughout the plant.
• Why do plants wilt on a hot day in terms of osmosis?


  Plants wilt because they lose water faster than they can absorb it, reducing turgor pressure.
• What are the key roles of osmosis in plants?


  • Water uptake from the soil
  • Maintenance of turgor pressure
  • Control of stomatal function
  • Nutrient transport
  • Contribution to cell growth
• What is the smallest unit of a chemical element?

  Atom
• What are the three subatomic particles that make up an atom?

  Protons, neutrons, and electrons
• What charge does a proton have?

  +1
• Where are protons located in an atom?

  Nucleus
• What is the charge of a neutron?

  0
• Where are neutrons found in an atom?

  Nucleus
• What charge does an electron have?

  • 1
• Where are electrons located in an atom?

  Orbitals
• How many protons, electrons, and neutrons does a hydrogen atom have?


  1 proton, 1 electron, 0 neutrons
• What is the nucleus of an atom composed of?

  Protons and neutrons
• What were the main gases in Earth's early atmosphere?

  Hydrogen, helium, nitrogen, carbon dioxide, methane
• What was the abundance of hydrogen in Earth's early atmosphere?

  • 80-90%