Laboratory Midterm Exam Flashcards
What does an angiosperm do?
Produces a seed that is enclosed in a fruit
How does an angiosperm perform its function?
Reproduces through flowers, undergoes double fertilization, and forms seeds within an ovary
What does a flower do?
its a reproductive structure for the plant
How doe a flower perform its function?
contains male and females organs to facilitate pollination and fertilization. The appearance of the flower attracts pollinators
Function of a carpel
the female reproductive structure that leads sperm down to the ovaries to fertilize
How does the carpel do its job?
receives pollen on the stigma, allows pollen tube growth through the style and houses the ovules in the ovary
function of the petal
colorful part that attracts pollinators
how does the petal do its job?
uses color, scent, nectar to attract bees, butterflies, and other pollinators
What is the function of a sepal?
to enclose and protect the flower bud
How does the sepal do its job?
prevents damage to the developing flower before blooming
What is the job of the stamen?
to produce out pollen to pollinate other nearby flowers
How does the stamen do its job?
produces and disperses pollen from the filament and anthers, pollinators pick up, or wind.
What is the job of the stigma?
to allow pollen for collection by pollinators
How does the stigma do this?
it tends to be sticky at the top so it can capture pollen
Function of the style
a tube-like structure that connects the stigma to the ovary
How does the style do its job?
it provides a pathway for pollen tubes to grow toward the ovary for fertilization
Function of the anther
produces the pollen grains
how does the anther do its job?
uses meiosis to create haploid pollen, which carries male gametes
Function of the filament?
supports the anther and fitness of the plant
How does the filament do its job?
positions the anther optimally for pollen dispersal
Function of the megasproangium
produces megaspores (female spores)
how does the megasporangium do its job?
undergoes meiosis to create a female gametophyte that houses the egg cell
Function of the microsporangium
produces microspores (male spores)
How does the microsporangium do its job?
undergoes meiosis to form pollen grains which carry sperm cells
What is the function of double fertilization?
angiosperms where two fertilizations events occur
How does double fertilization work?
one sperm fertilizes the egg, forming a zygote; the other fuses with polar nuclei to form endopserm
Function of the endosperm
feeds the developing embryo
how does the endosperm do its job?
formed by the fusion of a sperm nucleus with two polar nuclei, creating triploid tissue.
Function of the peduncle
to support a flower or flower cluster
How does the peduncle do its job?
holds the flower upright for optimal pollination and seed dispersal
Function of the seed coat
protects the seed
How does the seed coat do its job?
shields the embryo from damage, dehydration, and pathogens
function of a monocot
a group of flowering plant with one cotyledon
How does the monocot do its job?
has parellel leaf veins, scattered vascular bundles, fibrous roots, and flower parts in multiples of three
function of eudicot
a group of flowering plants with two cotyledons
how does the eudicot perform its function?
has net like leaf veins, ring arranged vascular bundles, a taproot system, and flowering parts in multiple of four or five.
function of the cotyledon?
a seed leaf that provides nutrients to the developing seedling
how does the cotyledon function?
stores or absorb nutrients to support early plant growth before photosynthesis begins
function of the root system
anchorage and absorption
how does the root system do this?
anchors into the ground via the taproot and lateral root extensions. Absorbs nutrients through root hairs.
Function of the shoot system
produces photosynthetic product, transports nutrients, and responsible for reproduction
How does the shoot system do this?
contains photosynthetic organs, flowers, and a complex vascular system
What does an internode do and why?
The internode is the segment between two nodes, which allows elongation and spearation of leaves and branches for optimal light exposure
What does a node do and why?
the parts of the stem where leaves, branches, flowers, attach. Contains meristematic tissue that enables new growth.
Leaf Blade: Function and How
the flat, expanded part of the leaf. It maximizes the surface area for photosynthesis.
Petiole: Function and Why
Attaches the stalk to leaf. It positions the leaf for optimal light capture and facilitates nutrient transport
Axillary Bud function and how
to grow vegetative shoots. contains meristematic tissue that divides into specialized cells.
Terminal (Apical) Bud: function and how
located at the tip of the stem, promotes vertical growth. Contains the S.A.M. Phenomenon of apical dominance
Epicotyl
the part of the embryo that develops into the shoot.
Hypocotyl
the part of the embryo between the cotyledons and the radicle. It forms the stem base and often bends to lift the cotyledons above the soil during germination
Coleoptile
A sheath protecting the young shoot in monocots. It helps push through the soil during germination while shielding the shoot tip
Coleorhiza
a protective covering around the radicle in monocots. Protects the root tip as it emerges from the seed.
Radicle
the embryonic root of a seedling. Its the first structure to emerge during germination, developing into the primary root.
Hypogeal Germination
a type of germination where cotyledon remain underground. Epicotyl elongates to push the shoot above the soil while the cotyledons stay buried.
Epigeal Germination
a type of germination where cotyledons emerge above ground. The hypocotyl elongates, pulling the cotyledons up, where they may aid in photosynthesis.
Cuticle
a waxy layer covering the epidermis of leaves and stems. It reduces water loss and protects against pathogens.
Epidermis
the outer layer of cells covering the leaves, stems, and roots. It acts as a barrier against water loss, pathogens, and mechanical damage.
Vascular Bundle
a transport structure in stems and leaves containing xylem and phloem. It conducts water, nutrients, and sugars throughout the plant.
Phloem
vascular tissue that transports sugars and organic molecules. It moves nutrients via pressure-flow from sources to sinks
Xylem
vascular tissue that transports water and minerals. It uses capillary action and transpiration pull to move water from roots to leaves.
Palisade Mesophyll
a layer of chlorophyll rich cells in leaves, that conducts photosynthesis due to high chloroplast density
Spongy Mesophyll
Loosely packed cells in leaves that allow for gaseous exchange due to the large spaces in between.
Stoma
small pores on the leaf surface for gas exchange, it opens and closes to regulate to co2 uptake and water loss
Guard Cells
specialized cells that control the opening and closing of stomata. When turgid, they open the stomata, and when taken up potassium, water follows because water follows solute
Axil
the angle between a leaf and the stem from which axillary buds grow. Allows for new lateral growth
Fruit
A mature that protects and disperses seeds.
Pericarp
The fruit wall derived from the ovary. Divides into three layers: exocarp, mesocarp, and endocarp.
Exocarp
The outer layer of the fruit. Protects the inner parts of the fruit and may have a tough, waxy, or hairy surface.
Mesocarp
The middle layer of the fruit.Often fleshy and stores sugars, aiding in fruit dispersal by attracting animals.
Endocarp
The innermost layer surrounding the seed. Can be hard (as in peaches) or soft (as in berries), providing seed protection
Aggregate Fruit
A fruit formed from multiple ovaries of one flower.
Each ovary develops into a separate fruitlet, forming a cluster (e.g., raspberry).
Dehiscent
A fruit that splits open to release seeds. Uses mechanical or environmental triggers to disperse seeds (e.g., pea pods).
Indehiscent
A fruit that does not split open. Seeds remain enclosed within the fruit (e.g., nuts, grains).
Capsule
A dry, dehiscent fruit that splits open along multiple seams.
Releases seeds through pores or slits (e.g., poppy).
Legume
A dry, dehiscent fruit that splits along two seams.
Found in the pea family (e.g., beans, peanuts).
Follicle
A dry, dehiscent fruit that splits along one seam.
Common in milkweed and magnolia plants.
Nut
A dry, indehiscent fruit with a hard shell.
Protects the seed and may be dispersed by animals (e.g., acorn).
Achene
A small, single-seeded, dry indehiscent fruit.
The seed is attached to the pericarp at one point but easily separates (e.g., sunflower seed).
Samara
A winged achene that aids in wind dispersal. The wing allows the seed to be carried by air currents (e.g., maple seed).
Grain
A small, single-seeded, dry indehiscent fruit where the seed is fused to the pericarp.
Common in grasses like wheat, corn, and rice.
Drupe
A fleshy fruit with a hard, stony endocarp (pit). Protects the seed and is commonly dispersed by animals (e.g., peach, cherry).
Pome
A fruit where the edible portion comes from the floral receptacle.
Seeds are enclosed within a core (e.g., apple, pear).
Berry
A fleshy fruit with multiple seeds.
The entire pericarp is soft and edible (e.g., tomato, grape).
Pepo
A berry with a thick rind.
Characteristic of cucurbits like watermelon and pumpkin.
Hesperidium
A berry with a leathery rind and juicy segments. Found in citrus fruits like oranges and lemons.
Aerial Root
A root that grows above ground.
Absorbs moisture from the air and supports the plant (e.g., orchids, mangroves).
Prop Root
An aerial root that provides structural support. Helps anchor plants in unstable soil (e.g., corn, banyan tree).
Storage Root
A root modified for storing nutrients. Stores starch, water, or sugars for later use (e.g., carrot, sweet potato).
Rhizome
An underground stem that stores nutrients and enables vegetative reproduction.Grows horizontally and produces new shoots and roots (e.g., ginger).
Corm
A swollen underground stem that stores food. Similar to a bulb but with a solid interior (e.g., taro, crocus).
Auxin
A plant hormone that regulates cell elongation, apical dominance, and phototropism. Transported down the stem, promoting growth by increasing cell wall plasticity and stimulating proton pumps.
Gibberellin
A hormone that promotes stem elongation, seed germination, and fruit development. Stimulates cell division and elongation, breaks seed dormancy, and triggers flowering.
Ethylene Gas
A gaseous hormone that regulates fruit ripening and leaf abscission. Accelerates the breakdown of cell walls and starches into sugars, making fruit soft and sweet.
Apical Dominance
The suppression of lateral bud growth by the shoot tip. Auxin produced at the tip inhibits lateral buds, ensuring vertical growth.
Apical Meristem
A region of actively dividing cells at the tip of roots and shoots.
Produces new cells for primary growth and elongation.
Tropic Response
A plant’s directional growth in response to external stimuli. Includes phototropism, gravitropism, and thigmotropism, controlled by hormone distribution.
Positive Phototropism
Growth toward light. Auxin accumulates on the shaded side, promoting elongation and bending toward the light.
Negative Phototropism
Growth away from light.
Typically seen in roots, where auxin inhibits elongation on the shaded side.
Positive Gravotropism
Growth toward gravity.
Roots grow downward due to auxin inhibition of cell elongation in the lower cells.
Negative Gravotropism
Growth away from gravity.
Shoots grow upward due to auxin-induced elongation in the lower cells.
Statoliths
Starch-filled organelles that help plants sense gravity. Settle to the lower part of cells, signaling the direction of gravity.
Leaf Abscission
The shedding of leaves.
Triggered by ethylene and reduced auxin, leading to the breakdown of cell walls in the abscission layer.
Abscission Layer
A specialized cell layer at the base of a leaf stalk where detachment occurs. Weakens due to enzymatic activity, allowing the leaf to fall.
Bolting
Rapid elongation of a flowering stem. Triggered by gibberellins when environmental conditions are favorable for reproduction.
