2.5 Ultrastructure of Plant Cells Flashcards
What is unique about plant cell ultrastructure compared to animal cells?
Plant cells have additional structures not found in animal cells, including a cellulose cell wall, chloroplasts, and a large central vacuole.
Describe the plant cell wall.
The plant cell wall is a rigid structure made mainly of cellulose, providing support, shape, and protection.
What are plasmodesmata, and what is their function?
Plasmodesmata are channels between plant cell walls that allow transport and communication between cells by facilitating the movement of substances.
Describe the structure and function of chloroplasts.
Chloroplasts have a double membrane and contain thylakoids stacked into grana, with stroma surrounding them; they perform photosynthesis, converting light energy into glucose.
What is the function of the large central vacuole in plant cells?
The central vacuole stores water, ions, and waste products and helps maintain cell turgor pressure, providing structural support.
What is the tonoplast, and where is it located?
The tonoplast is the membrane surrounding the central vacuole, controlling the movement of substances in and out of the vacuole.
What is the middle lamella in plant cells?
The middle lamella is a pectin-rich layer between adjacent plant cell walls, acting as a glue to hold cells together.
How do amyloplasts function in plant cells?
Amyloplasts store starch grains and convert starch into glucose when the plant requires energy.
What are pits, and what is their role in plant cells
Pits are regions in the cell wall with thin or absent cell walls that allow for the transfer of water and solutes between cells.
What is the function of the starch grains found in plant cells?
Starch grains are a storage form of glucose, providing an energy reserve that can be broken down when needed.
How does the cytoskeleton support plant cell function?
The cytoskeleton, composed of microfilaments, microtubules, and intermediate filaments, maintains cell shape, aids in intracellular transport, and organizes organelles within the cell.
