Biology Exam #3 Updated Actual Questions And Correct Answers

BIOLOGY EXAM #3 UPDATED ACTUAL QUESTIONS
AND CORRECT ANSWERS

Question:
1. What are the two major groups of seed plants? Which
group of seed plants evolved first? How do these plants
differ from ferns? What do they have in common with
ferns, but not mosses?

Answer:
-two major groups of seed plants: gymnosperms, angiosperms
-gymnosperms evolved FIRST
-the haploid spores of seedless plants are released by the parent and develop
independently, whereas seeds develop within the parental sporophytic tissue
-Seed plants have female spores (megaspores) and male spores (microspores)
-seedless plants do not bear seeds for propagation, whereas seed plants bear
seeds for multiplication
-Seedless plants multiply by spores that may produced asexually or as a
consequence of asexual reproduction
-The seedless plants reproduce by spores, while seed-bearing plants reproduce
by seeds.
-seed plants are similar to ferns as they are both vascular land plants while
mosses are nonvascular

,Question:
2. -radiation of angiosperms marks transition between Mesozoic era to Cenozoic
era-> earth became cooler and significant changes in terrestrial fauna and flora
occurred
-vascular seed plants that produce flowers and fruit
-most diverse of plants - 250,000 species
-monophyletic-- one phyla
-FLOWERS:
-bright colors
-attract pollinators with pay-off (nectar/sugar water)- nectar is not for themselves,
it is to attract, mutualistic relationship (pollinators=food, plants=reproduction)
-PARTS OF PLANT
-stamen (male): anther, filament
-carpel (female): stigma, style, ovary (ovary matures into fruit)
-ovule: where seeds develop
-ovary inside ovule, sporophyte tissue
*******gymnosperm doesn't have enclosed seed/tissue




Answer:
Angiosperms

Question:
3. Gymnosperms

Answer:
-naked seeds
-ovules (becomes the seed)
-enclosed by one integument (sporophyte tissue)
-rests on top of scales (ie: within cones)
-exposed at time of fertilization
-lack fruit (2nd integumentary around seed)
-heterosporous (seen in some seedless vascular plants)
-seed protects embryos
-reduced dependency on water
-sporophyte plant produces two types of spores
1. microspores->mitosis->male gametophyte
2. megaspores->mitosis->female gametophyte

, Question:
4. What exactly is a seed? What will it mature into when it
germinates? From what or where did it arise? What is/are
the difference(s) you see between the seeds of
gymnosperms and angiosperms?

Answer:
-seed: embryo is protected by extra layer of sporophyte tissue
-development of seed: fertilized gamete - embryo new sporophyte (diploid),
food (from female gametophyte), seed coat (derived from the parent sporophyte)
-seed plants originated about 360 million years ago
***seed plants break the ties with water for reproduction
EVOLUTION OF LAND PLANTS:
-1st group were ancestors to modern day mosses and liverworts
-2nd group seedless vascular plants
-3rd group seed vascular plants
-4th group evolved flowers and fruits
3 LIFE CYCLE MODIFICATIONS THAT CONTRIBUTED TO THE SUCCESS OF
TERRESTRIAL SEED PLANTS:
1. reduction of the gametophyte
-bryophytes: sporophyte dependent on large gametophyte
-pteridophytes: large sporophyte, small, independent gametophyte
-seed plants: reduced gametophyte, dependent on large sporophyte
-the gametophytes of seed plants develop within the walls of spores that are
retained within tissues of the parent sporophyte
2. development of the seed
-new sporophyte (diploid)
-food (from gametophyte)
-seed coat (derived from the parent sporophyte)
3. origin of the seed
-embryo is protected by extra layer of sporophyte tissue
-male gametophyte-> pollen tube->sperm
-Angiosperms have seeds that are enclosed within an ovary (usually a fruit), while
gymnosperms have no flowers or fruits, and have unenclosed or "naked" seeds on
the surface of scales or leaves.