Cell Specialisation Flashcards
Structure and function
What is the cuticle and its role?
Waxy layer prevents water loss
What is the role of the upper epidermis?
Protection, transparent to allow light through
What is the role of palisade mesophyll
Lots of choroplast for photosynthesis
What is the role of spongy mesophyll?
Losy packed cells with airspace for gas exchange
What is the role of the xylem?
Transport water and minerals absorbed from roots to leaves and stem
What is the role of phloem?
Transport food made from photosynthesis from leaves to rest of plant
What is the role of the stomata?
Controls water loss and gas exchange, they are pores
What is the role of the guard cells?
Controls the opening and closing of the stomata
What are air spaces for?
Gas exchange CO out and O in
Cytoskeleton- what is microfilaments made from?
Actin filaments
Cytoskeleton- what is intermediate made from?
Keratin
Cytoskeleton- what is microtubules made from?
Tubulin proteins
What can toipitent stem cells differentiate into
All cells
What can pluripotent stem cells differentiate into
Most but not all cells
What can multipotent stem cells differentiate into
Limited number of cell types
How do you work out volume?
Width X height X depth
How do you work out surface area?
Add up all the sides (enternal environment)
Adaptations of palisade mesophyll (6 marks question)
Near the upper surface of the leaf
Cylinder shaped, closely packed to absorb max light
At right angles to the surface of leaf to reduce the number of cross walls
Packed with large number of chloroplasts
Thin and transparent cell wall for max light penetration and higher diffusion of gases
Large surface area and moist cell surfaces for easier diffusion of gases
Large vacuole pushes choroplasts to edge of a cell
Adaptations of root hair cell (6 marks question)
Large surface area
Long and thin so they can penetrate between soil particles
Contain lots of mitochondria which provide energy for active transport
Channels and carrier proteins in cell membrane enable ions to cross membrane
Cytoskeleton functions
Aid in cell membrane and stabilize the cell
Aid transportation inside the cell
Helps the cell maintain its shape and support cell
Organized and tethers the organelles
