lecture exam 3 review questions Flashcards
How is Archaeplastida different from plants?
There is no difference, they are the same
Why are red algae red?
A pigment called phycoerythrin masks the green pigment of chlorophyll
What are red algae used for (by people)?
Nori - sushi (seaweed)
Carrageenan (thickening agent) - desserts, beer, shampoo, pet food, toothpaste
What’s a chlorophyte?
A group of green algae
Where do chlorophytes live? (3 places)
freshwater, damp soil, snow
What are the two life cycles of chlorophytes?
- Asexual
- Sexual - occurs when life is threatened (ex. lack of food) for quicker reproduction rates and variation
What 4 morphological traits support the sister-taxa relationship of charophytes and land plants?
- Rose-shaped complexes for cellulose synthesis
- Peroxisome enzymes for metabolism
- Flagellated sperm structure
- Phragmoplast formation
What 2 genetic datasets support the sister-taxa relationship of charophytes and land plants?
?
Four reasons to move to shallow water from deep.
- Sunlight
- More CO2
- Soils rich in nutrients
- Fewer herbivores and pathogens
Two challenges of land for plants.
- Scarcity of water
- Standing up
What is sporopollenin?
A durable layer polymer in charophytes that prevent exposed zygotes from drying out
What are the big 4 unique traits of land plants?
- Alternations of generations
- Walled spores produces in sporangia
- Multicellular gametangia
- Apical meristems
What is gametangia?
Tissue that produces gametes
What’s a cuticle?
Polyester and wax polymers that reduce water loss
What’s a secondary plant compound?
Acts as herbivore deterrent and UV protection, proven helpful for medicines
What’s a mycorrhizal fungus?
Fungi that have symbiotic relations with land plants, may have helped plants without true roots to obtain nutrients.
What does Chlamydomonas teach us about the benefits of sexual reproduction?
Increases diversity within a population & recombination of genes
Why are these dates important: 4.5 billion years ago (bya), 3.8 bya, 1.2 bya, 0.5 bya (500 million)
4.5 bya: origin of solar system and earth
3.8 bya: prokaryotes in water/origin of life
1.2 bya: cyano on land (biofilms); first multicellular species
0.5 bya: land plants (animals followed shortly after, but plants came to land first)
Why are gametes made via mitosis and spore via meiosis?
Gametes made via mitosis because they are already haploid and only need to split up/divide by 2
The gametophyte is haploid and produces haploid gametes by mitosis (multiply by 2)
Spores made via meiosis because they are diploid and need to become haploid
Fusion of the gametes gives rise to the diploid sporophyte, which produces haploid spores by meiosis
A spore has the ability to grow into adult gametophyte by itself - it does not need to interact with another cell to do this, all it needs to do is find favorable conditions.
* A gamete has to fuse with another gamete before it can for a zygote that can grow into the adult sporophyte
What are the three groups of nonvascular land plants?
Liverworts, hornworts, mosses
What does “vascular” refer to?
vascular tissue
Why are nonvascular plants so small?
They lack a vascular system
What are the 2 generations that alternate in land plants?
The diploid sporophyte and the haploid gametophyte.
What’s the generation that is obvious to us in nonvascular plants?
gametophyte (haploid)
Compare and contrast archegonia and antheridia. How are they alike? How are they different?
Archegonia: female gametangia, produce eggs and are the site of fertilization
Antheridia: the site of sperm production and release
Both: have something have something to do with reproduction and both have organs that can produce gametes
What is a sporangium?
organ that produces spores
What are the differences between a spore and a gamete?
A spore is a cell that can grow into an organism on its own. A gamete needs to fuse to become an organism
What is so special about an apical meristem?
It is where the plant actually grows. Differiante into different tissues.
Early fossil spores were not singular but in clumps of ________ (number?).
4
Why is vascular tissue important?
Transports organic and inorganic compounds allows the plant to grow big and tall.
What 3 groups are the nonvascular land plants?
liverworts, hornworts, and mosses
.What 2 groups form the seedless vascular plants?
Lycophytes (club mosses) Pterophytes (ferns and their relatives)
What 2 groups form the seed plants?
angiosperms and gymnosperms
.What’s a seed?
An embryo and nutrients surrounded by a protective coat
What’s a hepatophyta?
a liverwort which fits into the nonvascular land plant group
What’s an anthocerophyte?
a hornwort also a part of the nonvascular land plant group.
The ___________ is dominant in the nonvascular life-cycle.
gametophyte_
A spore develops into a____________.
gametophyte
Gametes fuse to eventually give rise to a___________.
zygote_
What does a bryologist study?
bryophytes
Why do moss need wet environments?
since mosses are non vascular they lack the tissue so they have not transport system, instead mosses most absorb water directly from the environment
Vascular tissue is necessary to ____________.
transport nutrients_
The two types of vascular tissues are_____________ and _____________.
xylem and phloem
Why do ferns do best in wet habitats?
Their spores will dry out if they are not in wet habitats.
What does homosporous and heterosporous mean?
Homosporous: one type of spore
Heterosporous: produce megaspores that give rise to female gametophytes and microspores that give rise to male gametophytes
What do the two types of vascular tissues do?
Xylem transports and stores water and nutrients. Phloem is responsible for transporting sugars, proteins and other organic molecules
What 3 things make up a seed?
Embryo
Food supply (storage tissue)
Protective coat
What are the 5 key adaptations of seed plants?
- Reduced gametophytes
- Heterospory
- Ovules
- Pollen grains
- Seeds
Why are these adaptations KEY for terrestrial life?
Seeds– allows them to produce without use of water
Pollen grains– able to disperse across great distances
What are the 3 parts of an unfertilized ovule?
Megasporangium
Megaspore
Integument
What is a pollen grain?
Sexual reproduction
the transfer of pollen to the part of seed plant containing the ovules
Angiosperm and Gymnosperm
Eliminates the need to transport through water
What is pollination?
reproduction
What are the 3 parts of a gymnosperm seed. If they have chromosomes, what are their ploidy levels?
Seed coat
Food supply (haploid) → n
Embryo (new sporophyte) → diploid (2n)
What are the four phyla of gymnosperms. Give an example of a plant from each.
Cycadophyta - cycas revoluta- looks like tiny palm tree
Ginkgophyta - Ginkgo biloba (pollen producing male tree
Gnetophyta - Mormon tea
Coniferophyta- Douglas fur- Bristlecone pine
Genus Ephedra (Mormon tea) produces the secondary plant compounds:
caffeine and ephedrine
Many conifer forests depend on _________ for survival.
fire ecology
Male spores of a pine tree are called __________ and develop into a____
microsporyte and gametophyte
Female spores are called __________ and develop into a___________.
megasporocyte and embryo
About how many species of angiosperms?
250,00
What are three key features of the gymnosperm life cycle?
Alternation of generations
Dominant sporophyte
Reduced gametophytes
What are the four major parts of a flower that are derived from specialized leaves?
Sepal
Petals
Stamens
Carpals
It can take nearly _______ years to go from cone to seed.
3
What is a major ecological problem with the message in the Smokey the Bear ad depicted at right?
It doesn’t allow fire ecology to happen
How does the grass stage of a longleaf pine survive a fire?
Grass stage - builds root system. Meristem protected by needles
Angion is greek for_______________.
seed
What’s a fruit?
fruit typically consists of a mature ovary but can also include other flower parts
Fruits protect seeds and aid in their dispersal
Mature fruits can either be fleshy or dry
Various fruit adaptations help disperse seeds
Seeds can be carried by wind, water, or animals to new locations
Why does a strawberry turn red?
Indicates to animals that fruit is mature and ready to be eaten; seeds are mature and ready to be spread
The male part of a flower is the___________ and has an_______ on top of a ______
stamen, anther and filament
What are the parts of a carpel?
An ovary/ovule, stigma, style
What’s an anachronistic fruit!?
Fruits out of time (animals today don’t really eat them)
Janzen would say that hedge apples and/or Guanacaste fruits are becoming more rare because_____________ are missing.
Gomphotheres - large elephants (now extinct) that would eat the apples and poop them out, therefore allowing them to reproduce.
What is corn silk?
Female part of corn
How did the ancestor of all of the Archaeplastida get its chloroplasts?
Secondary endosymbiosis
Monocots
More than one quarter of angiosperm species are monocots
Orchids, dat palms, lilies, barley
Eudicots
more than two-thirds of angiosperm species are eudicots
Poppies, pyrenean oak, dog rose, snow peas, zucchini flowers
What’s the difference between monocots and eudicots?
Monocots = parallel lines in leaves
Eudicots (dicots) = netlike lines in leaves
myzcorrhizal fungi?
Most land plants rely on mycorrhizal fungi to aid in the uptake of nutrients from the soil and these plants can even share using this network.
