Chapter 27: Prokaryotes
How do prokaryotes differ from eukaryotes?
Eukaryotes have a nucleus. Prokaryotes do not have a nucleus.
Describe the Domain Eukarya. What features distinguish a eukaryote? What organisms are eukaryotic?
organisms whose cells have a membrane-bound nucleus. All animals, plants, fungi, and many unicellular organisms are eukaryotes
what list of characteristics describes "land plants"
alternation of generations, with the haploid plant called a gametophyte, and the diploid plant called a sporophyte; protection of the embryo, formation of haploid spores in a sporangium, formation of gametes in a gametangium, and an apical meristem
Distinguish between homosporous and heterosporous. Are ferns homosporous or heterosporous? What is the relationship between heterospory and microspores/megaspores?
Homosporous: Male and female spores show no morphological difference
Heterosporous: (all seeded plants) have male and female spores that are physically different from each other.
Ferns are homosporous
Heterospory involves formation of two types of spores. Microspores are smaller in size and megaspores are much larger in size.
What are the major characteristics of the fungi?
-heterotrophs that feed by absorption
-multicellular or unicellular (such as yeast)
-they break down organic material and recycle vital nutrients
-decomposers, parasites, & mutualistic symbionts
How do gram-positive and gram-negative bacteria differ?
Gram-positive bacteria lack an outer membrane but are surrounded by layers of peptidoglycan many times thicker than is found in the Gram-negatives
Why is the Protista considered an artificial grouping?
They are miscellaneous eukaryotes, not closely related to each other and not sharing many characteristics, but not fitting any other kingdom of life
List some of the “problems” that plants had to overcome in order to live on land. What were some adaptations that evolved and enabled plants to overcome these “problems?
1. find a way to keep zygotes from drying out
2. structural support against gravity. To overcome this is Sporopollenin; cell plate (phragmoplast)
Why is the Carboniferous period significant to us today – as relates to the seedless, vascular plants and CO2 levels
when the vascular plants began to diversify; CO2 is important for humans to live
What is the morphology of a fungus?
made up of Mycelium, Hyphae, and a fruiting body
What is the basic morphology of a prokaryote?
Cell Wall, Flagella, DNA in a ring, Extreme Environments
Describe the nutritional diversity of protists.
autotrophy- involving plastids, photosynthesis, and the organism's manufacture of its own nutrients from the milieu
heterotrophy- the taking in of nutrients.
Be able to distinguish the following groups as nonvascular/vascular, no seeds/seeds, “naked” seeds/covered seeds: mosses/liverworts/hornworts, ferns, gymnosperms, angiosperms.
mosses/liverworts/hornworts: non vascular
ferns: seedless vascular
gymnosperms: Naked seeds
angiosperms: Covered seeds
Why can we say that the mosses and ferns are land plants that are still dependent on water for completion of the life cycle, but gymnosperms and angiosperms have “broken their dependence on water?”
Mosses and Ferns still have to have water for reproduction, as the sperms method for traveling. Gymnosperms are seed plants and therefore do not need water to reproduce.
list the common names of fungi we discussed in class and place them in the correct phylum.
“Molds” - mucromycetes
Mushrooms, puffballs - basidomycetes
morels, truffles - ascomycetes
Athlete’s foot, ringworm
Yeast: bread, alcoholic beverages
Penicillium
Describe the major modes of nutrition observed in living organisms
Autotrophic and heterotrophic.
Autotrophic –Plants synthesize their food by using light, carbon dioxide and water.
Heterotrophic – Both animals and human beings are called heterotrophs, as they depend on plants for their food.
What are the majors modes of locomotion among protists?
cilia, flagella, pseudopodia
For bryophytes: what does the term refer to in a general and specific sense, which multicellular stage is dominant
(3 phyla of nonwoody plants); gametophyte stage; require water for fertilization
What main features distinguish gymnosperms from angiosperms?
how their seeds are developed. The seeds of angiosperms develop in the ovaries of flowers and are surrounded by a protective fruit. Gymnosperm seeds are usually formed in unisexual cones, known as strobili, and the plants lack fruits and flowers.
Describe the major ecological roles of fungi.
decomposers, mutualist, parasites
How do prokaryotes in the Domain Bacteria compare to those in Domain Archaea?
Bacteria: cell membrane contains ester bonds; cell wall made of peptidoglycan; have only one RNA polymerase; react to antibiotics in a different way than archaea do.
Archaea: cell membrane contains ether linkages; cell wall lacks peptidoglycan; genes and enzymes behave more like Eukaryotes; have three RNA polymerases like eukaryotes; are extremophiles
in what ways are protists important to humans and ecosystems
in oceans, ponds, lakes, many protists are bottom-dwellers that attach to rocks and other substrates or creep through sand and silt. For the ecosystem they are consumed by small organisms in food chains and webs
For Monilophyta (Pterophyta): Why do we say that we now see a “typical” plant body? What is a common example of a pterophyte? Which multicellular stage is dominant? Know the parts of a fern plant.
vascular seedless ferns, sporocyte is dominant
What are some examples of gymnosperms and angiosperms?
gymnosperms: conifers or pinecones
Angiosperms: lilies, orchids
Describe the morphology of a lichen
crustose - crustlike, growing tight against the substrate.
squamulose - tightly clustered and slightly flattened pebble-like units.
foliose - leaflike, with flat sheets of tissue not tightly bound.