Cell Biology Quiz

Chapter 3: Electric Field and Charge

• Electric dipole: consists of one positive and one negative charge
• Conductors: have free electrons, electric field inside is zero, and electric potential is constant
• Electric field lines: outside a charged conductor, they are perpendicular to the surface
• Electric potential: decreases in the direction of increasing electric field
• Electric potential energy: depends on the path taken by the charge, and is a scalar quantity

Cell Biology

• Cellular organelles:
  • Mitochondria: responsible for cellular respiration
  • Ribosome: responsible for protein synthesis
  • Golgi apparatus: responsible for packaging and modification of proteins
  • Lysosome: responsible for intracellular digestion
  • Nucleus: responsible for storing genetic material
  • Endoplasmic reticulum: responsible for lipid synthesis
  • Cytoskeleton: responsible for cellular locomotion and structural support
  • Vacuole: responsible for storage of nutrients and waste products
• Cell membrane: regulates the entry and exit of substances in and out of the cell
• Cytoplasm: responsible for cellular metabolism and transportation

Motion

• Uniform motion: velocity is constant
• Non-uniform motion: velocity is not constant
• Displacement: distance from the initial to the final position
• Velocity: rate of change of displacement
• Acceleration: rate of change of velocity
• Uniformly accelerated motion: acceleration is constant
• Equations of motion:
  • Displacement: s = ut + (1/2)at²
  • Velocity: v = u + at
  • Acceleration: a = Δv / Δt

Electric Field

• Electric field: a region around a charge where another charge experiences a force
• Electric field intensity: the force per unit charge
• Electric field lines: imaginary lines that emerge from positive charges and enter negative charges
• Electric potential: the potential energy per unit charge
• Electric potential energy: the energy an object has due to its position in an electric field

Electric Potential

• Electric potential: a scalar quantity
• Electric potential energy: depends on the path taken by the charge
• Electric potential and electric potential energy: directly proportional

Conductor and Insulator

• Conductors: allow the flow of electric charge
• Insulators: do not allow the flow of electric charge
• Electric field inside a conductor: zero
• Electric field inside an insulator: not zero

Plant and Animal Cells

• Plant cells: have a cell wall, chloroplasts, and vacuoles
• Animal cells: lack a cell wall, have centrioles, and lack chloroplasts
• Cell wall: provides mechanical support and protection
• Chloroplast: responsible for photosynthesis

Other

• Coulomb's Law: the force between two charges is directly proportional to the product of the charges and inversely proportional to the square of the distance between them

• Electric dipole: a system of two equal and opposite charges### Physics

• An object in free fall near the surface of the Earth has an acceleration of approximately 9.8 m/s² downward.

• The acceleration of a car that starts from rest and reaches a speed of 20 m/s in 10 seconds is 2 m/s².

• Uniform motion is represented by the equation s = vt.

• The area under a velocity-time graph represents displacement.

• Speed is a scalar quantity, while displacement is a vector quantity.

• The electric potential at a point in an electric field where the electric field is zero is minimum.

Electric Charges and Fields

• The electric field at a point due to a negative charge is directed toward the charge.
• The electric field at a point due to a positive charge is directed away from the charge.
• Coulomb's law describes the force between two point charges.
• The electric potential energy of a system of two like charges increases when they are moved apart.
• The electric potential energy of a system of two unlike charges decreases when they are moved apart.

Cell Biology

• The mitochondria is responsible for the synthesis of ATP through cellular respiration.
• The cytoskeleton is responsible for cellular locomotion and structural support.
• The nucleus is responsible for storing genetic material and regulating cell activities.
• Lysosomes are responsible for breaking down excess or worn-out cell parts.
• Chloroplasts in plant cells are responsible for photosynthesis.

Other Key Facts

• The SI unit of charge is the Coulomb.
• The SI unit of electric potential is the Volt.
• Conductors allow the flow of electric charge, while insulators do not.
• The primary function of ribosomes is protein synthesis.
• Peroxisomes are responsible for detoxifying harmful substances in the cell.
• Vacuoles are responsible for storing nutrients and waste products.