FUNCTIONS & TYPES
one of the functions of roots are to produce various chemicals involved in growth and defense. true or false?
true
what is the lubricant that have been secrete to protect the roots from dried out?
mucilage
name the 3 zones
- zone of maturation
- zone of elongation
- zone of division
give the 3 root tissue systems
- cortical
- vascular
give 3 layers of cortex
- hypodermis
- storage parenchyma cells
- endodermis
a plant with a taproot can grow _____ to reach ____
deeply, water
how the root cells begin to elongate?
by filling their cell vacuoles with water.
where is the zone of cellular division occurs?
quiescent center
quiescent and meristematic cells are different in _______ to environmental problems such as _______.
sensitivity, radiation
the outermost layer of cells of cortex is ______ and the innermost layer of cortex is ________
hypodermis, endodermis
what are the 4 types of roots?
1. primary roots/ taproot
2. fibrous roots
3. adventitious roots
4. aerial roots
what is the composition of mucigel?
a hydrated polysaccharide containing sugars, organic acids, vitamins, enzymes, and amino acids.
what is the properties of mucilage that can help the roots to absorb water?
water-absorbing
why hypodermis is important in plant roots tissue systems?
to prevent the loss of water and nutrients which have been absorbed by the region of root hairs
which part of cortex that contain starch and have large intercellular spaces?
storage parenchyma cells
aerial roots grow from root tissue and may or may not be submerged in the soil. true or false?
false.
aerial roots are roots that are fully or partially exposed to the air. they grow not from root tissues, but from the plant's stem or leaf.
give 2 events that occur in zone of maturation
- cell differentiation
- root hairs formation
- secondary thickening
what are the functions of root cap?
- protects the root
- secrete mucilage to protects the root from becoming dried out
how the casparian strip form?
the radial and transverse cell walls of the endodermis cells are impregnated with lignin and suberin
stele is surrounded by a layer of cells called what? and what is the role of the cells in roots with secondary growth?
pericycle, becomes the meristematic tissue
give at least 3 functions of roots.
any:
• to anchor the plant to a substrate
• to absorb water and dissolved minerals
• to transport water or other compounds
• to store food reserves
• to produce various chemicals involved in growth (hormones) and defense (antimicrobial)
what are the name of cells that are arranged in columns?
columella cells
the ______ composition of mucilage helps the uptake of nutrient ions in the surrounding soil
chemical
what did the cell in the quiescent center function as to replace damaged cells of meristem? and why?
reservoir, and it is important because it organizes the patterns of primary growth in roots.
why the epidermis of the root lacks a cuticle?
to allow absorptions of water and salts from the soil.