Midterm #4 Flashcards
College Biology
What is the relationship between methanogens and grazing animals?
Methanogens are able to produce methane freely through the normal process of feed digestion.
Methanogens help in the breakdown of cellulose and play an important role in the nutrition of cattle.
Mutualistic relationship.
In what era did plants, fungi, and insects colonize the land? How many MYA was this?
Plants, fungi, and insects colonized the land 480 to 460 million years ago in the Ordovician period of the Paleozoic era.
What was the role of early autotrophic prokaryotes in early Earth?
Early autotrophic prokaryotes produced oxygen through photosynthesis.
Which group of algae are most closely related to plants?
A type of green algae called charophyte algae.
What is one unique feature about cellular slime molds?
The unicellular amoebae can combine to form a multicellular slug-like organism when they lack food.
How do you explain the similarity between seaweeds and plants?
Generally, seaweeds are not flowering plants, but like land plants, they contain chlorophyll and rely on photosynthesis to produce the food they need to survive.
When did eukaryotes first evolve?
At least 2.7 billion years ago.
Which group of bacteria tend to inhabit extreme environments?
Extremophiles are a group of microorganisms that possess the ability to tolerate and live under the extremes of physico-chemical, geological, and nutritional conditions.
What are the types of poisons that can be produced by pathogenic bacteria?
Exotoxins and endotoxins
How many millions of years ago did large, diverse multicellular organisms first appear in the fossil record? What era was this?
1.56 billion years ago - the Archean era
Describe the role of some prokaryotes as decomposers
Prokaryotes break down dead organisms in order to release nutrients back into the environment.
Describe the role of microbial communities within our bodies.
Bacteria in our gut are essential for breaking down our diet.
Why is RNA thought to have been the first genetic material?
RNA is capable of both storing genetic information and catalyzing chemical reactions.
How does Salmonella cause food poisoning?
Salmonella bacteria invade and destroy the cells that line your intestines
