Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
lecture10/11 part tw
plant devo part two
| Question | Answer |
|---|---|
| what are sieve cells? | long narrow cells that are alive at maturity. consists of chains of cells with end walls with pores for water flow (sieve plates) |
| describe sieve cells at maturity | fill with sieve tube sap and a thin layer of cytoplasm at cell periphery with remaining organelees |
| which organelles are lacking in a sieve cell? | nucleus, ribosomes, distinct vacuole |
| what is the role of companion cells? | to support a mature sieve cell. produced when parent cell divides and have all the organelles |
| describe companion cells in the phloem | load sugars in to sieve elements and help maintain functional plasma membrane in sieve elements |
| compare the apical and lateral meristem | apical - tips of roots and shoots/increase length/primary growth lateral - cyliner of cambium in roots and shoots/increases width, secondary growth |
| what are the basal meristems? | located belowground, important in species susceptible to fire or grazing |
| what are the three zones of primary growth in root meristems? | cellular division, elongation, and maturation (all behind the root cap) |
| hat is the zone of cellular division? | contains the apical meristem, where cells are actively dividing |
| zone of cellular elongation | cells recently derived from apical meristem...actively increasing in length |
| zone of cellular maturation | here older cells complete their differentiation into a type of tissue |
| what is the stele | consists of pericycle, xylem, and phloem |
| what is the pericycle? | one or more layers of undifferentiated cells..lateral roots arise here. outermost cell layer in vascular cylinder |
| compare the organization of the primary cells of eudicots and monocots | eudicots - star-shaped, between points are bundles of phloem, monocots - pith (parenchyma cells) lies at center and often stores carbohydrate reserves |
| what is the pith? | the center of the stem, consists of ground tissue that stores carbohydrates |
| what is the vascular bundle? | forms strands around the pith running the length of the stem |
| compare the vascular tissue of gymnosp, eudicots, monocots | gymno/eudicots - vascular tissue arranged in a ring. monocots - vascular bundles scattered throughout |
| palisade mesophyll cells | elongated/packed with chloroplasts/site of most photosynthesis/in leaves |
| sponge mesophyll cells | rounded/loosesly packed/often surrounded by air spaces near stomata. wet surfaces are site of gas exchange in plants |
| describes secondary growth in the tree trunk | increases root and shot width and provides structural support |
| what is the cambium | lateral mersistems, run the length of roots or stem and cells divide in a plane parallel to the long axis |
| what are the two types of cambium | cork and vascular |
| compare vascular and cork cambium | vascular- add cells on inside and outside. cork add cells on outside |
| how does the parenchyma transport materials? | laterally in stem via rays (conduct nutrients horizontally different than vessel elements that conduct water vertically) |
| where and when does the vascular cambium develop? | as primary growth proceeds between primary xylem and primary phloem |
| where does secondary growth begin | in older sections |
| what does the vascular cambium become? | secondary xylem and phloem, additional division creates rays of parenchyma cells |
| what does the cork cambium? | form the cortex, produces cork cells that replace epidermis. replaces itself from parenchyma cells |
| compare the secondary phloem and xylem | phloem transports sugars, degrades and gets replaced. xylem transports water and provides structural support |
| what is another name for the cork cambium? | periderm |
| how are tree rings added? | during periods of rapid growth, secondary xylem cells are large and thin-walled. during dormant periods they become small and thick-walled. this variation creates the annual growth rings |
| compare heartwood and sapwood | heartwood provides structural support but no logner transports water. sapwood includes active water conducting xylem tissue |
| describe the epidermis of tree trunks | periderm - cork cambium plus laters of cork cells it produces. bark - all the tissues external to the vasculary cambium including secondary phloem and periderm |
Created by:
nkjohnston1424
Popular Biology sets