exercise 9 Flashcards
capacity of life to give rise to a new life
reproduction
modes of reproduction
asexual and sexual
uniparental; no gametes are involved
asexual reproduction
undergoes mitosis
asexual reproduction
progenies are identical or clones of the parents; stability of characters and rapid increase in population
asexual reproduction
ex. of plant that undergoes asexual reproduction
kalanchoe pinnata
undergoes meiosis
sexual reproduction
meiosis halves the number of chromosomes and causes variation through:
-recombination
-independent assortment
-segregation of genes
two major processes of sexual reproduction
-meiosis
-fertilization/syngamy
process where haploid gametes fuse to form diploid zygote
fertilization/syngamy
progressive and cumulative changes that proceed over an organism’s life history
development
immediate product of fertilization; diploid cell
zygote
fusion/exchange of genetic material; happens when fertilization is absent
conjugation
what does conjugation form?
diploid zygospore
what are the major aspects of development?
-growth
-differentiation
-morphogenesis
increase in number of cells because of successive mitotic divisions and cell enlargement
growth
morphological and physiological changes in the cell; transforms meristematic into mature/adult form; associated with cell, tissue, or organ specialization
differentiation
progressive formation of a three dimensional shape or pattern that is characteristic of a species
morphogenesis
monocot flower
rice
dicot flower
gumamela (hibiscus rosa-sinensis)
gumamela
hibiscus rosa-sinensis
widely exhibited in bacteria, protists, plants, and lower forms of animals
asexual reproduction
modified fission wherein a new individual is derived from an outgrowth of the parent
budding
breaking up of a filament to give rise to segments that can produce new individuals; often occurs at weak points or next to a heterocyst
fragmentation
enlarged, thick-walled cell that can fix molecular nitrogen
heterocyst
reproduction of minute propagative cells called spores (meiospores)
sporulation
gemmae are formed within gemmae cups on the surface of the plant and develop into new plants when dispersed
gemmation
small clumps of undifferentiated cells
gemmae
cup shaped organs
gemmae cups
may produce new plants from modified stems and leaves
vegetative reproduction
types of asexual reproduction
-budding
=fragmentation
-sporulation
-gemmation
-vegetative reproduction
artificial methods
-cutting
-layering
-micropropagation
reproductive life cycle phases
-sporophyte
-gametophyte
produces spores through mitosis
sporophyte
produces gametes through meiosis; site of sporogenesis, gametogenesis, pollination, double fertilization
gametophyte
formation of spores
sporogenesis
where are male spores (microspores) located
stamen (microsporophyll)
where are female spores (megaspores) located
carpel/pistil (megasporophyll)
formation of gametophytes
gametogenesis
male gametophyte
pollen grain
female gametophyte
mature embryo sac
what is pollination
transfer of pollen grains from the anther of a plant to the stigma of another plant and is aided by agents since gametes are non motile
agents
wind, water, animals
what is double fertiization
fusion of one sperm cell and one egg cell to form a diploid zygote and fusion of another sperm cell and two polar nuclei to form a triploid endosperm
wind pollinated
anemophilous
insect pollinated
entomophilous
concerned with sporogenesis and gametogenesis
essential/reproductive structures
reproductive structures of a flower
stamen and pistil
do not participate in spore production
sterile/accessory structures
accessory structures of a flower
-petals
-calyx
perianth
-peduncle
-pedicels
-receptacle
collective form of petals
corolla
collective form of sepals; produce chemicals that ward off predators
calyx
composed of corolla and calyx
perianth
stalk that bears a cluster of flowers
peduncle
individual stalk; supports the flower
pedicels
all floral parts are attached to it
receptacle
protective structure that contains sperm cells
pollen grain
will grow down the style to the ovary
pollen tube
sticky platform
stigma
stamen is composed of:
anther, filament
carpel is composed of:
stigma, style, ovary
where does double fertilization take place?
ovary
opening of the ovule
micropyle
where cells divide through meiosis
ovule
what does the ovule produce
1 egg, 2 polar nuclei
explain double fertilization
once the pollen tube reaches the micropyle(opening of the ovule), it releases two haploid sperm cells. one sperm cell fuses with one egg cell to form a diploid zygote. another sperm cell fuses with two polar nuclei to form a triploid endosperm. the diploid zygote will divide to produce and embryo while the endosperm will nourish it.
what happens to the rest of the surrounding ovule after double fertilization?
develops into a protective seed coat
a seed consists of:
-external seed coat
-internal structures (embryo, endosperm)
usually develops from the ovary tissue to provide additional protection
fruit
stages of plant development
-fertilization up to seed maturation
-seed germination up to plant maturation
types of plant development
-determinate (close)
-indeterminate (open)
grows to a certain size and stops, eventually undergoing sensescence and death
determinate
parts of plant that has determinate development
leaves, flowers, fruits
presence of meristematic tissues in the mature plant; continuous development
indeterminate development
parts of plant with indeterminate development
root, shoot meristems
influence plant growth
plant growth regulators
plant growth regulators
-auxins
-gibberellins
-cytokinins
-inhibitors
-ethylene
what seeds were used to examine the morphology of a dicot plant?
-baguio/kentucky beans
-sitaw
baguio;/kentucky beans
phaseolus vulgaris
sitaw
vigna unguiculata sesquipedalis
peculiar scar at the center; point of attachment to the funiculus; (dicot seed)
hilium
small pore or opening beside the hilium (dicot seed)
micropyle
opposite the micropyle; ridge-like structure formed by the part of the funiculus that is adnate to the ovule (dicot seed); channel for nutrient transportation
raphe
two fleshy structures (dicot seed)
cotyledons
small leaf-like structure that is connected to the hypocotyl (dicot seed); harbors delicate beginnings of future leaves and stems
plumule
stem-like structure connected to the plumule and attached to the radicle; center
hypocotyl
root-like projection attached to the hypocotyl; where tip of hypocotyl lies
radicle
parts of a dicot seed
-hilium
-micropyle
-raphe
-cotyledons
-plumule
-hypocotyl
-radicle
monocot seed
zea mays
yellow portion; bulk of the seed (monocot)
endosperm
light colored; base (monocot seed); holds genetic imprint
embryo
inactive stage when seeds form
dormancy
what happens once dormancy is broken
seed germinates
seed germination is a result of the following:
-imbibition of water through micropyle
-increased metabolic rate
-assimilation and respiration
-active cell division and growth
-rupture of the seed coat
-sprouting of the embryo
what are the types of germination based off of
position of seed leaves (cotyledons) during the emergence of the embryo
types of germination
epigeal and hypogeal
type of germination wherein cotyledons emerge from the ground and undergo photosynthesis that provides food until true leaves are formed
epigeal
cotyledons remain below the ground because of substantial food reserves in the seed
hypogeal
types of plant growth
primary and secondary
plant growth that is a result of cell division in apical meristems found in shoots and roots; growth in length
primary growth
growth in width (thickness); result from the production of new cells by lateral meristems
secondary growth (secpndary tissues)
lateral meristems
vascular cambium; cork cambium
visible growth layers formed by primary xylems; formed when tree trunks increase its diameter
rings
how are the ages of trees determined?
estimated by counting the number of rings
accompanied by the formation of reproductive organs which enable plants to propagate
maturation of plants
protective layer of a dicot seed
testa
mung bean
vigna radiata
stages of development of a gumamela
-immature stage
-bud stage
-anthesis stage
-final anthesis stage
-senescence stage
-flower separates from plant
this leads to flower development
subsequent mitosis
generate microspores and megaspores
heterosporous