Plants Flashcards
(39 cards)
Lichen
first species to inhabit an area
What are the three reasons that plants adapt quickly?
Sexually reproduce
Have short generation times
Have a lot of offsprings (seeds)
What are the closest relatives of plants?
Green algae called charophytes are the closest relatives of plants
What 3 traits do plants share with charotypes
Rings of cellulose-synthesizing proteins
Structure of flagellated sperm
Formation of a phragmoplast
What are the 5 main plant traits that are absent in charotypes?
- alteration of generation
- multicellular dependent embroys
- Walled spores produced in sporangia
4.Multicellular gametangia - Apical meristems
Alteration of Generation
In most plants, there is a life cycle that alternates between two multicellular stages: a haploid (n) gametophyte stage and a diploid (2n) sporophyte stage.
Multicellular Embryo
After fertilization, the zygote develops into a multicellular embryo that remains attached to and dependent on the parent plant.
This protects the developing embryo and provides it with nutrients.
Sporangia
In plants, spores are produced in multicellular structures called sporangia, which protect and disperse the spores.
Multicellular Gamentangia
Gametangia are structures that produce and protect gametes. In plants, these are multicellular structures that enclose the gametes, protecting them from desiccation and mechanical damage.
Apical Meristems
regions of actively dividing cells located at the tips of shoots and roots.
- They are responsible for the growth of plant tissues, allowing plants to grow outward (lengthen) without becoming taller.
Cuticle
waxy layer on the outer surface of the epidermis that helps reduce water loss from the plant’s surface
Stomata
small pores on the underside of plant leaves that allow for gas exchange, enabling the plant to take in carbon dioxide for photosynthesis and release oxygen and water vapor
Seed
an embryo and nutrients surrounded by a protective coat
Spore
embryo with only a little nutrients
What characteristics do seed plants have (4)
Reduced gametophytes - gametophyte generation is much smaller and less conspicuous than the sporophyte generation
Heterospory - means they produce two types of spores: megaspores (female) and microspores (male).
Ovules (egg)
Pollen (sperm)
Seeds provide some evolutionary advantages (3)
–They may remain dormant for days to years, until conditions are favorable for germination
-They have a supply of stored food
–They may be transported long distances by wind or animals
Bryophytes
small, non-vascular, seedless plants that include liverworts, mosses, and hornworts.
What stage are bryophytes usually in?
The sporophyte stage is short-lived and only occurs during reproduction,
Peat Moss
type of bryophyte
- known for its ability to store large amounts of carbon and is sometimes used as a fuel source
What is the ecological role of bryophytes
stabilizing soil, retaining moisture, and providing habitat for various organisms.
Xylem
carries water and minerals from the roots to the rest of the plant.
pholem
carries food, such as sugars and amino acids, produced by photosynthesis in the leaves, to other parts of the plant.
Seedless vascular plants
ferns, lycophytes, and monilophytes, are larger than bryophytes and reproduce using spores rather than seeds.
- they have roots and leaves
- spend more time in diploid sporophyte stage than haploid germophyte stage
What are the two types of seed vascular plants?
Gymnosperms
Angiosperms