Paper 2 - Topic 6, Plant Structures And Their Function Flashcards
What are auxins
A group of plant hormones that inhibit growth in plant roots and stimulate growth in shoot tips
What is biomass
The total mass of organic material, measure in a specific area over a set period
Which hormone stimulates ripening in fruits
Ethene
What is gravitropism
A plants growth response to gravity
What are guard cells
Cells that surround the stomata and change shape depending on the volume of water, they control the rate of transpiration by becoming turgid or flaccid
What is lignin
A material that strengthens the walls of xylem cells
What is a limiting factor
A variable that limits the rate of a particular reaction
What is the lower epidermis
A layer of cells on the leaf’s lower surface that contains stomata and guard cells
What is negative plant tropism
The growth of a plant away from a stimulus
What is the palisade mesophyll layer
The main photosynthesis tissue in plants located below the upper endodermis, it receives the most light so contains the greatest concentration of chloroplasts
What is the phloem
A transport tissue found in plants that is specialised to transport sugars from the leaf to the rest of the plant in both directions
What is photosynthesis
An endothermic reaction that takes place inside photosynthetic organisms and converts light energy into chemical energy
What is the equation for photosynthesis
6CO2 + 6H2 ——> C6H12O6 + 6O2
What is phototropism
A plants growth response to light
What is plant tropism
The growth response of a plant to a stimulus
What are root hair cells
Specialised cells responsible for the uptake of water and minerals from the soil, they have long hair-like extensions known as root hairs, provide a large surface area for absorption
What is the spongy mesophyll layer
A type of loosely packed mesophyll tissue with air pockets specialised for gas exchange, also contains chloroplasts for photosynthesis