Cell specialization

• What are the roles of stem cells in multicellular organisms?

  Stem cells are involved in growth, repair, and differentiation into specialized cells.
• How are differentiated cells adapted to their specialized functions?

  Differentiated cells have unique structures and functions that suit their roles in the organism.
• What is the process of cell specialization following fertilization?

  • Production of unspecialized cells
  • Development into specialized cells through differentiation
• What are the properties of stem cells?

  Stem cells are undifferentiated cells with unlimited capacity to divide and differentiate.
• Where are stem cell niches located in adult humans?

  In locations such as bone marrow and hair follicles.
• What is the difference between totipotent, pluripotent, and multipotent stem cells?

  Totipotent stem cells can develop into any cell type, pluripotent can differentiate into all cell types except an embryo, and multipotent can form a limited range of cells.
• What is the definition of a zygote?

  A zygote is a totipotent stem cell formed by the fusion of sperm and ovum.
• What happens to the zygote during the first five days after fertilization?

  The zygote develops into a blastocyst through cell division.
• What type of stem cells are found in a blastocyst?

  Embryonic stem cells
• What is the role of morphogens in embryonic development?

  Morphogens regulate gene expression and determine the type of specialized cell based on their concentration.
• How do morphogens create a concentration gradient in tissues?

  Morphogens are produced and released from embryo cells and diffuse through tissues, creating a gradient.
• What is the significance of the surface area-to-volume ratio in cells?

  The surface area-to-volume ratio affects the efficiency of material exchange across the cell membrane.
• How does cell size relate to its function in multicellular organisms?

  Cell size varies to optimize functions such as nutrient exchange and specialized roles.
• What are the implications of the surface area-to-volume ratio for growing cells?

  • As cells grow, volume increases faster than surface area.
  • This can limit the cell's ability to exchange materials efficiently.
  • Cells may divide when surface area is insufficient for metabolic needs.
• What are the smallest and largest cells in the human body?

  Sperm are the smallest, and ova (egg cells) are the largest.
• What is the diameter of red blood cells?

  Red blood cells have a diameter of 6 to 8 µm.
• What is the range of sizes for striated muscle fibers?

  Striated muscle fibers can range in length from a few millimeters to several centimeters.
• How do scientific models help in understanding complex systems like cell size?

  Scientific models simplify complex systems, allowing for analysis of relationships like surface area and volume.
• How can students model the relationship between surface area and volume?

  Students can create model cells using cubes of different sizes to observe the relationship.
• What is the surface area-to-volume ratio for a cube with edge length 2 units?

  1. 1
• What happens to the surface area-to-volume ratio as a cell grows?

  The surface area-to-volume ratio decreases as the cell grows.
• What is the primary function of the plasma membrane in a cell?

  The plasma membrane is responsible for the exchange of materials and heat between the cell and its environment.
• What is the main site of metabolism within a cell?

  The cytoplasm is the main site of most metabolism within the cell.
• What are the advantages of small size and large size in biological systems?

  Small size allows for efficient material exchange, while large size can support complex functions.
• How do cells become differentiated?

  Cells become differentiated through the expression of specific genes while suppressing others.