BI266 Lecture Notes - Lecture 3: Gravitropism, Solution, Cuticle
Document Summary
Function of roots: anchor plants into soil, absorption of water and minerals, store food or water, other specialized functions, cu(cid:272)ur(cid:271)ita(cid:272)eae (cid:862)(cid:272)u(cid:272)ur(cid:271)its(cid:863) roots that store water (cid:374)ot just food. Tiny small vacuoles merge into 1 or 2 large vacuoles, occupying more than 90% of volume of each cell. If a cambium is present, increase in girth happens through the addition of secondary tissues: region of maturation - cells differentiate into various distinctive cell types. Root hairs: formed from epidermal cell extensions with thin cuticle, absorb water & minerals, adhere tightly to soil particles. Increase total absorptive surface of root: cuticle exists on root but not root hairs. Cortex- parenchyma cells between epidermis and vascular cylinder: mostly stores food. Pericycle - outer boundary of vascular cylinder: continues to divide, even after mature, forms lateral (branch) roots and part of the vascular cambium.
