study guide exam 1 Flashcards
What are the two prokaryotic domains and how are they classified?
- Archaea and bacteria.
- Archaea:cell membrane contains ether linkages; cell wall lacks peptidoglycan; genes and enzymes behave more like Eukaryotes; have three RNA polymerases like eukaryotes; and extremophiles
- 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.
How are protists defined?
-Protists were the first eukaryotes. many prokaryotes today have infoldings of the plasma membrane. the eukaryotic internal membrane system, called the endoplasmic reticulum (ER), and the nuclear envelope may have evolved from such infoldings of the plasma membrane, encasing the DNA of prokaryotic cells that gave rise to eukaryotic cells.
What are the metabolic options for prokaryotes?
- oxygenic, producing oxygen and 2. anoxygenic, nonoxygen producing. anoxygenic photosynthesis involves the formation of products such as sulfur and sulfate instead of oxygen. prokaryotic cells are also the only chemolithotropic organisms, meaning that they use the energy stored in chemical bonds of inorganic molecules to synthesize carbohydrates.
- photoautotrophs: use light as an energy source
- chemcolithoautotrophs: oxidize inorganic compounds.
- photoheterotrophs: use light as an energy source and organic compounds as carbon sources
- chemoheterotrophs: use organic compounds for both energy and carbon.
- oxygenic, producing oxygen and 2. anoxygenic, nonoxygen producing. anoxygenic photosynthesis involves the formation of products such as sulfur and sulfate instead of oxygen. prokaryotic cells are also the only chemolithotropic organisms, meaning that they use the energy stored in chemical bonds of inorganic molecules to synthesize carbohydrates.
What is symbiosis and what are the different forms it can take?
- symbiosis is the ecological relationship between different species that live in direct contact with each other.
- mutualism: a form of symbiosis in which both parties benefit. ex. nitrogen-fixing bacteria with plant roots
- commensalism: one organism receives benefits while the other is neither benefited nor harmed. ex.H2S bacteria on hydrovent worms
- parasitism: one member benefits, and the other is harmed. ex. ticks
How are seeds similar and different in gymnosperms and angiosperms?
-Angiosperms, also called flowering plants, 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. Gymnosperm seeds are often configured as cones. The characteristics that differentiate angiosperms from gymnosperms include flowers, fruits, and endosperm in the seeds.
What are the major adaptations that plants made as they made the transition from purely aquatic to terrestrial organisms?
- Vascular tissue
- Plants have been able to spread their vascular tissue farther, thus allowing them to obtain more water and nutrients when they are far from a body of water. This allows them to grow taller, increased access to sunlight, as well as decrease the access of neighboring (and competing) short plants to sunlight.
Sporophyte generation
-increased dependency of the sporophyte generation, plants grow larger
Gametophyte generation
-decreased size of the gametophyte generation. Increased dependence of the gametophyte on the sporophyte.
Spores
-allows them to spread by wind dispersal instead of relying on water.
Antheridia
-increased protection of the embryo.
Are you able to you explain sexual and asexual reproduction and give an example of each (from algae or plants)?
- asexual reproduction: the process by which an individual inherits all of its chromosomes from a single parent, thus being genetically identical to that parent; cell division is by mitosis only. ex. whole plants can be cloned by regenerating plant cells or tissues on nutrient medium with growth hormones.
- sexual reproduction: the process of producing offspring through an alternation of fertilization (producing diploid cells) and meiotic reduction in chromosome number (producing haploid cells). ex. flower plants
What are the three characteristics of true of mosses and vascular plants?
- Have sporic life cycle with alternation of generations.
- Have a protective layer around the egg (and zygote and embryo).
- Have sporopollenin coating spores.
- Have sporic life cycle with alternation of generations.
What are juniper berries?
female seed cone produced by the various species of junipers
Why was the potato famine pathogen so fatal? What recent discovered was just made about this pathogen (Science Friday Topic 2)?
there was a parasite that infected the potatoes and ruined the crops to the point where they went extinct. this caused many Irish immigrants to move to America
How is the distribution between dermal, ground, and vascular tissue distinct in a root, stem, and leaf?
-dermal tissue, primarily epidermis, is one cell layer thick in most plants, and it forms an outer protective covering for the plant. ground tissue cells function in storage, photosynthesis, and secretion, in addition to forming fibers that support and protect plants. vascular tissue conducts fluids and dissolved substances throughout the plant body.
What is the mature male and female gametophyte in a i) pine tree (gymosperm) versus and ii) pea plant (angiosperm)?
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What are the three ways bees are sensing/attracted to flowers to pollinate them (Science Friday Topic 3)?
-color, electromagnetic field, scent
What is the difference between a simple, aggregate, and multiple fruit and can you give an example of each?
- simple: simple fruits can be either dry or fleshy, and result from the ripening of a simple or compound ovary in a flower with only one pistil. Ex. peach
- aggregate: a fruit formed from several carpels derived from the same flower, e.g., a raspberry.
- multiple: a fruit formed from carpels derived from several flowers, such as a pineapple.
What is the difference between indehiscent and dehiscent fruits?
-in dehiscent fruits the mature ovary wall (pericarp) breaks open thereby freeing the seeds. in indehiscent fruits the seeds remain in the fruit after the fruit has been shed from the parent plant.
