Studied by 8 people
how are plants described as roots (essay)
main root (taproot), then secondary roots (lateral roots), these arise from vascular cambium. root hair is a projection of a dermal cell, that absorbs minerals. There are aerial/prop roots that grow above ground
tissue types role for photosynthesis
dermal tissue have protective epidermal cuticle and guard cells and stomata that lets an exchange of photosynthetic gasses throughout the cell. ground tissue have parenchyma mesophyll that contain tightly packed chloroplasts for efficient capturing of light. Vascular tissue have phloem that transport sugars/ photosynthetic products throughout the plant to supply all parts with necessary materials and nutrients.
vascular cambium
main growth tissue in roots and stems of plants-widens stem
cross section: root or stem?
roots are circular, stem cells have ring-shape
summarize how shoots grow longer, fatter and branch
they grow at the tips, branch from vascular cambium, as it gains more minerals, half of new cells extend root, other half are pushed forward into soil. grow in growth at secondary meristem
stem
shoot, support plant, conduct minerals and nutrients to plant
apical bud
tip of the shoot, produces plant hormones auxin to grow axillary bud
axillary bud
allow branching of plant
node and internode
part of stem where one or two leaves emerge, internode is the distance between two successful nodes
primary/epical meristem
often suppresses lateral meristems
meristem
tissue found at tips of roots and shoots that actively divide cells to form new tissue
cork cambium
widens epidermis so plant can keep growing during secondary growth
secondary growth
growth in girth by lateral meristems from cork and vascular cambium ex: wood growth, xylem and phloem working
simple leaves
a single leaf
compound leaves
two or more distinct leaflets
doubly compound leaves
twice divided, leaflets are on secondary vein that divided from a branch of the main branch
petiole
attaches leaf to stem
leaf blade
helps plant move and store photosynthesis products
leaf vein x/p
xylem transports water and minerals, cell products like energy are transported via phloem
primary growth
rapid growth at meristems
pinnate
one main vein
palmate
several main veins
apical dominance
inhibitory control exercised by the apical portions of the shoot over the growth of the lateral buds below
determine vs indeterminate growth
determinate: plants stop growing after flowering. indeterminate growth: plants continue growing after flowering
stamen
whorl that is male part of flower, contains filament and anther
anther
produce and spread pollen
filament
carry nutrients to anther
carpel/pistil
female part of plant, contains stigma, style, ovary, ovule
stigma
collects pollen
style
prevents incompatible pollen from entering ovary
ovary
prepare for fertilization, protect zygotes
receptacle
thickened section of flower stem where flower organs grow from
petal
whorl that attracts pollinators
sepal
outer whorl for protection
angiosperm life cycle
diploid until meiosis, micro/megasporangia produce haploid pollen, mega/micro gametophyte processes lead to fertilization. sporophyte dominant
what is double fertilization?
two sperm cells unite with two cells in female gametophyte (embryo) to form the zygote and endosperm
seed dormancy and imbibition
adaptation where they are inhibited from sprouting even though they are ready-until they get the signal that everything is okay. Imbibition- when water is given to seed, so it can germinate.
hypocotyl
portion below cotyledon
epicotyl
portion above cotyledon
cotyledon
near embryo, provides plant nutrients to grow
seed dispersal for fruits methods (2)
wind and animals
Asexual (vegetative) reproduction in plants:
Fragmentation and apomixis
sexual reproduction in plants, and term for when they cannot:
self fertilization & self incompatibility
How humans have impacted plants:
genetic engineering: resistance genes, changing molecularly. Selective breeding: GMOS, etc.
cloning and cutting, why?
cloning to produce identical plants quickly/economically, cut at base to grow more healthy leaves, make it bushier
Note
Flashcard