4: Green Algae Flashcards
Green Algae
1) How many known species
2) Are they mostly aquatic or terrestrial
3) What are the three major groups
4) Which are only marine
1) 20 k
2) Mostly aquatic
3) Ulvophyceae, Chlorophyceae & Charophyceae
4) Ulvophyceae
Define Mitosis
Part of the cell cycle in which chromosomes in the nucleus duplicate to produce two identical sets of chromosomes each of which ends up in its own nucleus
Define Karyokinesis
Where nucleus envelope reforms around chromosomes
Cytokinesis
Divides the cytoplasm, organelles & cell membrane
Meiosis
type of cell division required for reproduction in eukaryotes where the number of chromosomes is halved (usually from
2n to n, but many plants are polyploids
Cell cycle
1) What is the shortest part?
2) What is the longest part?
1) Mitosis
2) Interphase
Steps of Cell cycle
1) Interphase
2) Mitosis
3) Telophase & Cytokinesis
Cell cycle
1) What is the shortest part?
2) What is the longest part?
1) Mitosis
2) Interphase
Mitosis Steps
Interphase Prophase Later prophase Metaphase Early anaphase Anaphase Telophase Later telophase
Prophase
Chromatin condense into chromosomes
Metaphase
Chromosomes align in the middle
Anaphase
Chromosomes split
Telophase
Spread to poles
Nuclear envelop reforms (karyokinesis
Telophase & Cytokinesis
(animal cell
1) Microfilaments form around center
2) Microfilaments constrict forming cleavage
3) Cell completely pinched by microfilaments
Telophase & Cytokinesis
(plant cell
1) Carbohydrate rich vesicles around center
2) Vesicles fuse & cell pate forms
3) Cell plate completely formed, creates two separate cells
Open mitosis
During pro-metaphase the nuclear membrane disintegrates;
both animals and plants
Closed Mitosis
the Spindle (microtubles) form inside the nucleus or the microtubules penetrate the nuclear membrane and the membrane stays intact. (most algae)
Persistent Telophase Spindle
a mitotic spindle that persists through
telophase until cytokinesis
Non-persistent Spindle
A spindle that disintegrates during telophase
Phragmoplast
set of short microtubules oriented parallel to the spindle microtubules (PERPENDICULAR), it catches dictyosome vesicles & guides them to the site where the new cell plate is forming.
Phycoplast
a set of microtubules oriented PARALLEL to the plane of the new cell wall and involved in wall formation.
Furrowing
Pinching in the cell to divide
Plasmodesmata
Microscopic channels that connect cells of all
higher plants and some green algae
Why do plants need plasmodesmata?
For cell communication & exchange content through the channels through the cell wall (which is quite impermeable)
-no single celled algae have these as there is no other cell for it to communicate with
Flagella apparatus between:
1) Chlorophyceae
2) Ulvophyceae
3) Charophyceae & Land Plants
1) Symmetrical root system
2) Symmetrical root system
3) Asymmetrical root system
Mitosis between:
1) Chlorophyceae
2) Ulvophyceae
3) Charophyceae & Land Plants
1) Closed non-persistent spindle
2) Closed non-persistent spindle
3) Open persistent spindle
Cytokinesis between:
1) Chlorophyceae
2) Ulvophyceae
3) Charophyceae & Land Plants
1) Furrowing phycoplast (some with cell plate & plasmodesmata 2) Furrowing 3) Furrowing (some with cell plate, phragmoplasts & plasmodesmata)
