Angiosperms Flashcards
How many species of angiosperms are there?
Over 300 000 species
Is anthophyta monophyletic?
Definitely
What are the 2 main classes that encompass 97% of all angiosperms?
Monocots and eudicots
How are the dicots related to other angiosperms?
They have two cotyledons, but the group branched off sooner than the other two. Eudicots and monocots are sister groups, and if we put everything with two cotyledons in one group it would be paraphyletic
What are the 6 traits that differentiate monocots and eudicots?
Pollen grain furrows
Number of flower parts
Cotyledons
Leaf venation
Primary vascular bundle arrangement in the stem
True secondary growth with vascular cambium
How are monocots and eudicots different in terms of pollen grain furrows?
Monocots have 1 furrow, eudicots have 3
How are monocots and eudicots different in terms of number of flower parts?
Monocots have flower parts in multiples of 3, eudicots have multiples of 4 or 5
How are monocots and eudicots different in terms of cotyledons?
Monocots have 1 cotyledon, eudicots have 2
How are monocots and eudicots different in terms of leaf venation?
Monocots have parallel venation, eudicots have net-like venation
How are monocots and eudicots different in terms of primary vascular bundle arrangement in the stem?
Monocots are scattered, eudicots are arranged in a ring
How are monocots and eudicots different in terms of true secondary growth?
Very rare in monocots, common in eudicots
Why is true secondary growth so rare in monocots?
Because of the scattered arrangement of the vascular bundles. Since secondary growth occurs around the vascular bundle, any growth around one bundle will disrupt the other bundles
Where is the microgametophyte found in angiosperms?
In the anther
Where is the megagametophyte found in angiosperms?
Don’t have one, been completely reduced to 7 cells: the polar nuclei, 3 antipodal cells, 2 synergids
