Plant Tissues Flashcards
Describe upper and lower epidermis
Very thin layer of cells which cover upper and lower leaf
= protects surface of the leaf
Adaptations of epidermis
Transparent
= allows light to pass through the photosynthetic cells below
Covered with a waxy cuticle
= reduces evaporation of water on surface of leaf
= prevent leaf from drying out
Where is stomata
Tiny pores in lower epidermis
Stomata function
Allow co2 and o2 to enter and leave the leaf
Control water vapour that can pass out of the leaf
Function of palisade cells
Contain lots of chloroplasts
= chloroplasts contain chlorophyll
= absorbs light energy needed for photosynthesis
Adaptation of spongy mesophyll
Contains lots of air spaces
= allow co2 to diffuse from stomata through mesophyll to palisade cells
Xylem function
Transports water from roots to stems and leaves
Also transports dissolved mineral ions
= magnesium used to make chlorophyll
Involved in transpiration
Phloem function
Transports dissolved sugars produced by photosynthesis from leaves to rest of plant
= sugars used immediately
= eg glucose used in respiration
Define translocation
Movement of sugars and other molecules through phloem tissue
Where is meristem tissue
Found at growing tops
Eg shoots and roots
Importance of meristem tissues
Contain stem cells
= can differentiate into different types of plant tissue
Products of respiration in plants
Ethanol
Carbon dioxide
Structure of xylem
Made of dead cells
End walls of cells are broken down
= long tube to transport minerals and water
Hollow
Contains cytoplasm
Contains lignin
Structure of phloem
Made of living cells
Have pores in end walls (sieve plates)
= allow sugars to move through cell interior
Companion cell connected by pores
= mitochondria in companion cell provide energy for cell
Transport up and down plant
Similarities of phloem and xylem
Both made of cells
Both tubular
