Plant Structure and Growth Flashcards
Similarity of apical and lateral meristems
Both apical and lateral meristems rely on totipotent cell divisions for growth this increases plant volume & mass
Node
A point in a plant stem at which one or more leaves are attached
What is the function of plant roots?
absorb water and mineral ions, anchor plant to the ground
What is the function of stems?
provides attachment for leaves ( at nodes ), transports nutrients
What is the function of a plants leaves?
perform photosynthesis, gas exchange and transpiration
What is the one non-vascular plant studied?
phylum brophyta
Describe phylum bryophyta
Non-vascular plant, small, lack leaves and stems, no xylem or phloem tissue, produces using spores
What is an example of a phylum Bryophyta?
moss and liverworts
describe vascular plants
have conductive vascular tissue, xylem and phloem
What are the types of vascular plants studied?
Spermatophytes, phylum filicophyta, phylum angiospermophyta, and phylum Coniferophyta
Describe spermatophytes
produce seeds
Describe Phylum Filicophyta
has pinnate leaves, reproduces using spores released from sori
Example of a Phylum Filicophyta
Ferns
Describe Phylum Angiospermophyta
flowering plants
Example of Phylum Anigospermophyta
sunflower
Describe a Phylum Coniferophyta
seeds are in cones ( naked seeds )
Example of a Phylum Coniferophyta
Conifers
Phylum Angiospermophytas are either…
monocots, or dicots
Monocots
one seed leaf ( grass, orchids )
Dicots
Two seed leaves ( roses )
What do undifferentiated cells in the meristems allow?
undifferentiated cells in the meristems of plants allow indeterminate growth
Meristems
tissues containing totipotent/ undifferentiated cells capable of indeterminate growth
indeterminate growth
allows a plant to go through mitosis to grow and add new structures forever, as long as resources are accessible
What are the 3 most basic tissues?
Dermal tissue, ground tissue, and vascular tissue
Vascular tissue
xylem transports water and minerals and provides support, and phloem transports sugars and provides support
What are the two types of meristems?
Apical and Lateral
Apical Meristem
primary growth
Where is the apical meristem found?
found at the apex tips of roots and stems
What is the function of apical meristems?
Allows plants to grow taller and produce new leaves, flowers, fruits, and allows roots to extend throughout the soil
Lateral Meristem
Secondary growth
Where are lateral meristems found?
One the side, in the cambium
What is the function of lateral meristems?
Allows plant stems and roots to grow outward, become thicker, and produce secondary phloem and xylem cork and bark
Compare and contrast apical vs lateral meristems growth location
Apical growth: occurs at the apex/tips of stems and roots
Lateral growth: occurs at cambium in woody trees/shrubs
Compare and contrast apical vs lateral meristems directional growth
Apical meristem: adds vertical growth to roots and stems
Lateral meristem: adds lateral growth, widens and thickens, stems and roots of plants
Compare and contrast the end products of apical vs lateral meristems
Apical meristem: produces new leaves and flowers/fruits
Lateral meristem: produces bark and wood on trees/ woody shrubs
Compare and contrast apical vs lateral meristems developmental growth
Apical meristem: develops into primary xylem and phloem
Lateral meristem: produces secondary xylem and phloem
What do plant hormones control?
Plant hormones control growth in the shoot apex
Phytohormones
plant hormones
How is auxin produced?
produced by cells in the shot apex ( apical meristem )
Auxin
main plant hormone promotes growth in the shoot apex by inhibiting growth in the lateral/ axillary buds
Auxin
main plant hormone promotes growth in the shoot apex by inhibiting growth in the lateral/ axillary buds
Where are apical and lateral meristems found?
Apical and lateral meristems are found in dicots and gymnosperms (woody plants)
tropism
a directional response in a plant to an external stimulus ( light, chemicals, gravity, touch )
Positive tropism
plant growth is toward the stimulus
Negative tropism
Plant growth is away from the stimulus
phototropism
is a positive and negative tropism in plant stems
What is phototropism controlled by?
Auxin
What do high concentrations of auxin stimulate?
in stems and shoots, high concentrations of auxin stimulate cell elongation and growth by changing patterns of gene expression
Auxin efflux pumps
actively transport auxin out of cells to redistribute it within plant tissues, creating auxin concentration gradients and causing certain plant tissues to contain higher concentrations of auxin than others
How does auxin influence cell growth rates?
auxin influences cells growth rates by changing the pattern of gene expression
Micropropogation
a technique used to asexually reproduce large numbers of identical plants
What does micropropagation utilize?
micropropagation of plants utilizes tissues from the shoot apex, nutrient agar gels, and growth hormones
What is micropropagation used for?
Micropropagation is used for rapid bulking of new charities, production of virus-free strains of existing varieties, and propagation of orchids and other endangered species
Shoot apex
The shoot apex is the tip of the stem, which contains meristematic cells and the region of growth
