Module 19: Introduction to Plants Flashcards
How do scientists classify plants?
- With or without embryo protection
- With or without vascular tissue (vascular vs non vascular)
- with or without seeds (seed or nonseed)
- With or without flowers. (angiosperms/flower or gymnosperms/cones
What is a cuticle?
An adaptation on most above ground plant parts. A fatty coating on the outer surface of their cells.
What are stomata?
Openings in the outer cell layer of leaves and some stems. Enable the exchange of gases even with a cuticle.
What is vascular tissue?
Specialized transport tissue
What are vascular plants?
Plants that have vascular tissue
What are nonvascular plants?
Lack specialized transport tissues and instead move substances by osmosis and diffusion.
What is a seed?
A plant structure that contains an embryo and nutrients for the embryo. Covered with a protective coat.
What are the divisions of Nonvascular plants?
Bryophyta - Mosses
Anthocerophyta - hornworts
Hepaticophyta - liverworts
What are the characteristics of bryophytes?
Produce rootlike, multicellular rhizoids for support, anchorage, and absorption of water and minerals
substances move by osmosis and diffusion.
Sphagnum and other plants together form peat, which is important for fuel and in gardening
successful in harsh evironments
What are the characteristics of anthocerophyta?
Smallest division of nonvascular plants
Horns are actually sporophytes
Substances move by osmosis and diffusion
Each cell of the gametophyte and sporophyte has one large chloroplast
Often found in a mutualistic relationship with cyanobacteria
What are the characteristics of hepaticophyta?
Named for their appearance and use as a medicine a long time ago. Found in many habitats, including tropical and arctic
Substances move by osmosis and diffusion
Have unicellular rhizoids
DNA analysis suggests liverworts are the most primitive land plant.
What are rhizoids?
root hairs. Kind of like roots, but mainly just in nonvascular plants, only for anchoring.
What is a strobilus?
A compact cluster of spore-bearing structures
What are the divisions of seedless vascular plants?
Lycophyta - club “mosses”
pterophyta - ferns and horsetails
What are the characteristics of lycophyta?
Descendants of the oldest vascular plants
ancient lycophytes were up to 30 meters tall; their remains are part of the coal we use for fuel
Sporophyte generation is dominant
Many are epiphytes, plants that live anchored to another plant. Some draw moisture right from thei air.
What are the characteristics of pterophyta?
Dominant sporophyte generation
ferns have a thick underground stem that is used to store food
treelike ferns were dominant during the carboniferous period; their remains are also much of the coal we use today
Horsetails produce spores in strobili at the tips of reproductive stems.
What are cotyledons?
Structures that either store food ar help absorb food for the tiny sporophyte. Seeds have one or more of these
What are the divisions of nonflowering seed plants?
Cycadophyta
Gnetophyta
Ginkgophyta
Coniferophyta
What are the characteristics of cycadophyta?
Resemble palm trees
LIve in the tropics and subtropics
Only one species is native to the United States.
What are the characteristics of gnetophyta?
Can live as long as 1500-2000 years
Welwitschia has only two leaves and a large storage root
Ephedra is the only genus found in the United States
What are the characteristics of ginkophyta?
represented by only one species, Ginkgo biloba
male and female trees; females produce bad smelling berries
Pollution-resistant, grow well in urban areas
What are the characteristics of coniferophyta?
Includes pines, firs, and redwoods
Economically important
Adaptations include needlelike leaves to conserve moisture.
What are the three types of plant cells?
Parenchyma
Collenchyma
Sclerenchyma
What are the functions of parenchyma?
Storage
Photosynthesis
Gas exchange
Protection
Tissue repair and replacement
What are the functions of collenchyma?
support
transport of materials
What are the functions of sclerenchyma?
support for surrounding tissues
flexibility for plant
tissue repair and replacement
What is the epidermis?
The layer of cells that makes up the outer covering on a plant. AKA dermal tissue. Resemble pieces of a jigsaw puzzle.
What are guard cells?
The two cells that form a stoma, open and close the stomata.
What are trichomes?
Hairlike projections on leaves and stems that leave a fuzzy appearance, protect the plant from insect and animal predators.
What are root hairs?
increase a roots surface area and enable the root to take a in a greater volume of materials.
What is xylem?
The water-carrying vascular tissue composed of specialized cells called vessel elements and tracheids. Water flows freely through a system of xylem.
WHat are vessel elements?
tubular cells that are stacked end-to-end, forming strands of xylem called vessels. Open at each end with barlike strips across the openings. Only transports materials away from roots
What are tracheids?
long cylindrical cells with pitted ends, found end-to-end and form a tubelike strand. Less efficient than vessel elements.
What is phloem?
The main food-carrying tissue that transports sugars and other organic compounds throughout a plant. Both directions. Consists of sieve tube members and companion cells
What is a sieve tube member?
Contains cytoplasm but lacks a nucleus and ribosomes.
What is a companion cell?
Has a nucleus, next to sieve tube members.
What is ground tissue?
consists of parenchyma, collenchyma, and sclerenchyma cells. Tissue that is not meristematic, dermal, or vascular.
What is a root cap?
Covers the tip of a root, consists of parenchyma cells.
What is the cortex?
The layer below the epidermal layer. Composed of ground tissues involved in transport and storage.
What is the endodermis?
A layer of cells at inner boundary of the cortex, cells are inside a waterproof strip called a Casparian strip, which creates a barrier that forces water and dissolved minerals to pass through endodermal cells rather than around them.
What is the pericycle
Next to the endodermis produces lateral roots.
What are the types of roots?
Taproots - thick root with smaller, lateral branching roots
Fibrous roots - rapid water storage
Modified root - anchors plants
pneumatophores - supplies oxygen to submerged roots
adventitious/prop roots - supports plant stems
What are the types of stems?
Tuber - food storage, ie, white potato
Rhizome - asexual reproduction/food storage, ie, ginger
Runner - asexual reproduction, ie, spider plant
Bulb - food storage, Ie, narcissus
Corm - food storage, ie, crocus
What is a petiole?
A stalk that attaches the blade of a leaf to its stem.
What is a palisade mesophyll?
A tissue in the leaf made up of column-shaped cells that contain many chloroplasts. Under the upper epidermal cell layer.
What is the spongy meophyll?
The layer beneath the palisade mesophyll that consists of irregularly-shaped, loosely packed cells with spaces surrounding them.
What is transpiration?
A process in a leaf that helps pull the water column upward. Water evaporates from the inside of the leaf to the outside.
What are the types of leaves?
Simple - not divided into smaller parts
Compound - divided into leaflets
What are the types of leaf venation?
Palmate, pinnate, and parallel.
What are the types of leaf arrangements?
Opposite, alternate, and whorled
What is a nastic response?
A plant response that causes movement that is not dependent on the direction of the stimulus. Not a growth response, is reversible, and can be repeated.
What is a tropism?
A plant’s growth response to an external stimulus
Positive vs negative tropisms
Positive tropisms result in plant growth toward the stimulus while negative tropisms result in plant growth away from the stimulus.
What are some tropisms?
phototropism - light, positive toward the light source
gravitropism - gravity, positive downward growth, negative upward
Thigmotropism - mechanical, positive growth toward point of contact.
What is vegetative reproduction?
A form of asexual reproduction in which new plants grow from parts of an existing plant. New plants are clones of the original plant.
What are gametophytes and sporophytes?
They are alternations of generation in some organisms. They rotate between being haploid gametophytes and diploid sporophytes. Gametophytes produce eggs or sperm (gametes) and sporophytes produce spores.
What are flowers’ four organs?
Sepals, petals, stamens, and pisils.
What are sepals?
A flower organ that protects the flower bud. Often looks like small leaves.
What are petals?
Usually colorful structures that can attract pollinators and provide them with a landing platform
What is a peduncle?
A flower stalk that sepals and petals are attached to.
What are stamens?
Male reproductive organs in most flowers.
What is the filament of a stamen?
The stalk that supports the anther.
What is the anther of a stamen?
Contains cells that undergo meiosis, which forms pollen grains. Two sperm form inside each pollen grain.
What is the pistil?
The female reproductive organ of a flower, found in the center of a flower.
What parts make up the stamen?
The filament and the anther
What parts make up the pistil?
The stigma, the style, and the ovary
What is the stigma?
The tip of the pistil where pollination occurs
What is the style?
The part that connects the stigma to the ovary
What is the ovary?
Contains one or more ovules, where female gametophytes develop and an egg forms inside those.
What’s the difference between complete and incomplete flowers?
Complete flowers have all four organs. Incomplete flowers are missing one or more.
What’s the difference between perfect and imperfect flowers?
Perfect flowers have both stamens and pistils, imperfect flowers have only have one.
What’s the difference between eudicot and monocot?
Eudicot flowers have a multiple of four or five petals, as well as other organs. Monocots have flower organs in multiples of three.
What’s the difference between eudicot and monocot?
Eudicot flowers have a multiple of four or five petals, as well as other organs. Monocots have flower organs in multiples of three.z
What is the endosperm?
A tissue that forms as a result of 3n cell divisions. It provides nourishment for the embryo.
What is the seed coat?
A protective tissue that forms when the endosperm matures and the outside layers of the ovule harden.
What are the types of fruit?
Simple fleshy fruits - one or more seeds, i.e. apples or peaches
Aggregate fruits - Flowers with multiple female organs that fuse as the fruits ripen, i.e. raspberries, blackberries
Multiple fruits - form from many flowers that fuse as the fruits ripen - i.e. pineapples, figs.
Dry fruits - fruits are dry when mature, i.e. nuts or grains.
What is germination?
The process when an embryo in a seed starts to grow.
What is a radicle?
The first part of the embryo to appear outside the seed, starts absorbing water and nutrients.
What is the hypocotyl?
The region of the stem nearest the seed, the first part of the seedling to appear above soil.
What is dormancy?
A period of little or no growth, increases the survival rate of seeds exposed to harsh conditions.
