Botany Exam 1

life

complex and dynamic, organized and self-sustaining, cellular, information based, can adapt and evolve

plant vs. animal cells

contain cell wall, dictyosome, chloroplasts, large vacuoles, lack true intermediate filaments

prophase 1

chromosomes coil and become shorter and thicker, nuclear envelope dissociates, homologous chromosome begin to pair, spindle fibers attach to centromeres, crossing over can occur

metaphase 1

pairs of chromosomes align at equator of the cell, spindle complex completes formation

anaphase 1

each chromosome migrates to a pole of a cell, separates chromosome pairs with each pole getting two chromatids

telophase 1

chromosomes partially revert back to their interphase status, nuclear envelope may or may not reform, nucleolus reappears, two cells formed

prophase 2

chromosomes recondense

metaphase 2

centromeres of the chromosomes align along the equator of the cell, spindle apparatus reformed

anaphase 2

chromatids separate and migrate to opposite poles

telophase 2

chromatids re enter interphase state, nuclear envelope and nucleolus reform, 4 new cells with half the DNA of the original cell formed

apical meristem

found near tip of roots and shoots, consists of protoderm, ground meristem, and procambium, produce primary tissues

parenchyma

most abundant cell type, usually contain large vacuoles, usually will have air spaces between cells, may contain chloroplasts, can be involved in transfer of substances between cells, can be long lived, retain the ability to replicate

collenchyma

have thicker cell walls, found just below the epidermis, provide additional structural support that is flexible, can be long lived

sclerenchyma

thick cell walls, impregnated with lots of lignin, dead at maturity, fibers and sclereids

sclereids

sometimes found distributed in other tissue types, can be random or specific to certain tissue regions, aka stone cells

fibers

elongated shape, used in the making of textiles, rope, string, canvas, etc.

complex tissues

composed of at least two types, vascular tissue of plants, epidermis

xylem cells

composed of parenchyma, fibers, vessels, tracheids, and ray cells

phloem cells

consists of sieve tube members, companion cells, parenchyma, fibers, and ray cells

xylem

conducts water and minerals absorbed by the roots system, up the plant

vessel elements

part of xylem, part of a long tube like element, roughly cylindrical in shape, open at both ends, irregular secondary wall development, perforation plate between end cell walls, dead at maturity

tracheids

part of xylem, have a tapered shape, have pits in their sides, allow for lateral transfer of water, dead at maturity

ray cells

long lived parenchyma, help in lateral movement of water and in food storage

phloem

conducts photosynthetic and other anabolic products from the leaves, down the plant

sieve tube members

form sieve tubes, have perforated end plates, are living cells, at maturity lack nucleus, ribosomes, or vacuole, will form callus plugs from callose, form when leaves drop or under pathogen attack

companion cells

aid in conduction of food, keep the sieve tube members alive by providing biomolecules

protoderm

gives rise to the epidermis

procambium

appears inside the protoderm, produces the primary xylem and phloem tissue

ground meristem

produces parenchyma cells, pith in the center of the stem, cortex

simple leaves

leaves that have a single blade

compound leaves

leaves divided into leaflets

pinnately compound

leaflets in pairs along an extension of the petiole called the rachis

palmately compound

leaflets attached to a point at the end of the petiole

pinnately veined

one primary vein located in a midrib

palmately veined

multiple primary veins fanned out from a singular point

monocots veins

veins run parallel to one another

taproot

thick tapered root, thinner bran roots appear from taproot, dicots

fibrous

many small roots of equal diameter, arise from adventitious roots, monocots

food storage roots

store carbohydrates for later growth

water storage roots

used to supplty water in periods without

propagative roots

adventitious buds, can develop into aerial stems called suckers, can be separated and grown into a new plant

pneumatophores

spongy root tissue extended up out of the surface of the water, allows for direct exchange of gases

aerial roots

provide additional structural support

contractile roots

roots that pull the shoot portion of the plant into the soil over time

buttress roots

provide stability for plants in shallow soils

parasitic roots

some plants “feed” off of other species of plant they are in contact with

photosynthetic parasitic roots

typically only gain water and minerals

nonphotosynthetic roots

not true saprophytes

haustoria

peg like protrusions that penetrate the host

stem

consists of an axis with attached leaves

alternate

alternating sides of the stem or in a spiral

opposite

arranged in pairs on either side of the stem

whorled

arranged in groups of three or more

decussate

opposite leaves that alternate to form a cross

nodes

regions of leaf attachment, leaf is usually attached by a petiole

blade

flat part of the leaf

internode

region between leaf attachment points

axil

angle formed between the stem and the petiole, can be the location of the axillary bud

axillary bud

meristematic tissue, can become additional stems or flowers, protected by bud scales

stipules

paired leaf-like appendages at the base of the petiole, typically very small if present

terminal bud

often present, responsible for growth lengthening the stem

leaf scars

found in deciduous plants that have lost their leaves for the season

bundle scars

from vascular connection between stem and leaf