Lab exam 2 Flashcards
What are angiosperms?
Angiosperms are plants whose seeds develop inside of a fruit.
The term angiosperm translates to seed container, referring to the seeds developing within a fruit.
What is a carpel?
The carpel contains the megasporangia which ultimately produce female gametophytes.
A complete flower has carpels; incomplete flowers may lack either the carpel or the stamen.
What is the function of cones in conifers?
Conifers produce spores in cones which are clusters of modified leaves.
There are two types of cones: ovulate cones and pollen cones.
What is the role of the cuticle in plants?
The cuticle restricts water loss to the stomata and is a feature of leaves.
Thicker cuticles are common in plants growing in drier environments.
What does dioecious refer to?
Dioecious refers to gametophytes that develop from heterospores in seed plants.
What is endosperm?
Endosperm is an energy source absorbed by the seed leaves (cotyledons).
It provides nutrition for the embryo until it can photosynthesize.
Define gymnosperm.
Gymnosperms are seed plants that have ‘naked’ seeds which develop from exposed ovules.
What is a megagametophyte?
Megaspores germinate into female megagametophytes retained within the ovules of seed plants.
The mature female megagametophyte develops within the ovaries of the carpel.
What does a megasporangium produce?
A megasporangium produces megaspores through the division of a single megasporocyte by meiosis.
What is a megasporocyte?
A megasporocyte is a large cell within the megasporangium that divides to produce four haploid megaspores.
What are microgametophytes?
Male microgametophytes are also known as pollen grains.
They develop within the microsporangia located in the anthers of flowering plants.
What is a microsporangium?
Microsporangia are structures where male microgametophytes (pollen grains) develop.
What is a microsporocyte?
A microsporocyte is a cell within the microsporangium that will produce haploid microspores.
All cells within the microsporangia are diploid until meiotic divisions are complete.
What is an ovulate cone?
An ovulate cone is a structure where ovules develop and contain megasporangia.
What is an ovule?
An ovule is the megasporangium and the integument surrounding it, which develops into a seed after fertilization.
What is a pollen cone?
A pollen cone is a structure that produces thousands of microgametophytes or pollen grains.
What is a sorus?
A sorus is a cluster of sporangia on the lower surface of leaflets of a mature fern sporophyte.
What does a stamen contain?
The stamen contains the microsporangia and ultimately produces male gametophytes.
Antheridia
Specialized structure in plants where haploid sperm are produced by the male gametophyte
Apical meristem
Growing point at the tips of roots and shoots responsible for primary growth (increase in length)
Archegonia
Specialized structure in plants where haploid eggs are produced and where fertilization occurs by sperm
Archegonia
Specialized structure in plants where haploid eggs are produced and where fertilization occurs by sperm
Dormancy
A state of reduced metabolic activity in seeds or spores that allows them to survive unfavorable conditions
Gametangium
A multicellular structure in plants where gametes (sperm or eggs) are produced. Examples include antheridia and archegonia.
Gametophyte
The multicellular haploid (n) generation in the alternation of generations life cycle of plants that produces gametes through mitosis
Haplodiplontic
A type of life cycle in plants characterized by an alternation between a multicellular haploid (gametophyte) generation and a multicellular diploid (sporophyte) generation. Also known as alternation of generations.
Heterospory
The production of two distinct types of haploid spores by the sporophyte: megaspores (which develop into female gametophytes) and microspores (which develop into male gametophytes). Seen in seed plants and some seedless vascular plants.
Homospory
The production of one type of haploid spore by the sporophyte, which typically develops into a gametophyte that may produce both sperm and eggs. Seen in nonvascular plants and most seedless vascular plants.
Megaspore
A larger haploid spore produced by a heterosporous plant that develops into a female gametophyte (megagametophyte)
Microspore
A smaller haploid spore produced by a heterosporous plant that develops into a male gametophyte (microgametophyte or pollen grain)
Pollination
The transfer of pollen (male gametophyte) to the part of a seed plant containing the ovules (e.g., stigma of a flower or ovulate cone)
Pollen
In seed plants, the male gametophyte enclosed within a protective coat. Contains cells that will generate sperm.
Seed coat
The protective outer layer of a seed that develops from the integument of the ovule
Sporangium
A multicellular structure in plants where diploid sporocytes undergo meiosis to produce haploid spores
Spore
A haploid reproductive cell with a thick wall (often containing sporopollenin) that is capable of developing into a new organism (gametophyte in plants) without fusion with another cell. Produced by meiosis in the sporangium.
Sporocyte
A diploid cell within a sporangium that undergoes meiosis to produce haploid spores
Sporophyte
The multicellular diploid (2n) generation in the alternation of generations life cycle of plants that produces haploid spores through meiosis
Thallus
A plant body that lacks true roots, stems, or leaves. Characteristic of nonvascular plants.
