Lecture 4 Flashcards
For more than the first ____ years on Earth’s history, the terrestrial surface was lifeless.
3 Billion
What is responsible for supplying oxygen and being the ultimate source of most food eaten by land animals?
Plants
What thing is responsible for making the atmosphere we now enjoy possible and also what is on the bottom of most food webs on the planet?
Plants; they capture solar energy and covert it to a form that is usable by other life forms.
What are the divisions of ancestral algae?
Red Algae-Chlorophytes-Charophytes-Embryophytes. RCCE
Land plants evolved from _____; plants evolved from _____ generally, but more specifically from _____.
Green Algae-Protists-Green Algae
What are the notable adaptations allowing charophytes’ move to the land?
Charophyte ancestors lived at the waters’ edge where they had access to high light availability, nutrient rich soil, fewer herbivores, and fewer pathogens.
But, land presented challenges: a scarcity of water and lack of structural support.
In charophytes (and their ancestors) a layer of a durable polymer called sporopollenin prevents the exposed zygotes from drying out.
What are the divisions of land plants?
Bryophytes-Pteridophytes-Gymnosperms-Angiosperms. BP-GA
The evolution of charophytes moves towards _____ dependence on free water and a seed stage that is _____ packaged in a protective coat.
Less-More
What are some general common features between charophytes and land plants?
Multicellular-Eukaryotic-Photosynthetic-Autotrophic-Cell walls are made of cellulose-Many biochemical details.
What are 4 distinctive traits that are shared only with Charophytes and land plants?
- Rings of cellulose-synthesizing proteins.
- Peroxisome enzymes.
- Structure of Flagellated Sperm
- Formation of a phragmoplast. RP-FP
What can be said about the proteins that synthesize cellulose in non-charophyte algae?
They have linear sets of proteins that synthesize cellulose.
What are 4 key traits that appear in nearly all land plants but are absent in the charophytes?
- Alternation of Generations
- Walled Spores produced in the sporangia.
- Multicellular Gametangia
- Apical Meristems
What are some important things to note about alternation of generations?
- Plant embryos develop from zygotes retained on the parent (gametophyte)
- Embryo has placental transfer cells which enhance nutrient transfer.
- Analogous to embryo-nutrient transfer interface in placental mammals.
- Land plants sometimes called embryophtyes.
What do placental transfer cells do?
They enhance nutrient transfer.
What are land plants sometimes called?
Embryophytes.
Are spores diploid or haploid?
Haploid
Where are spores produced?
The sporophyte produces walled spores in organs called sporangia.
What do spore walls contain and what is the role of that mechanism?
They contain sporopollenin, which makes them resistant to harsh environments.
Where are the gametes produced?
Gametes are produced within organs called gametangia.
Female gametangia, called _____, produce _____ and are the site of _____.
Archegonia-Eggs-Fertilization
Male gametangia, called _____, are the site of sperm production and release.
Antheridia.
From where to where does sperm move in plants and what is a necessary factor that needs to be present?
Sperm travel from Antheridia to the Archegonia. MUST HAVE WATER TO TRAVEL (SWIM).
Plants sustain continual growth in their _____.
Apical Meristems
TRUE OR FALSE: Cells from the apical mersitems differentiate into various tissues.
TRUE
