BIOL 1309 Chapter 14
population
A group of individuals of the same species that live in the same area and interact with one another is a
Mechanical isolation
A male snail and a female snail from different species attempt to mate, but the orientation of their different types of shells prevents mating from occurring.
True or false. Bacteria reproduce by an asexual process in which one parent cell gives rise to identical daughter cells.
True
There are four bacteria in an egg salad that is left out at room temperature. After two hours, how many bacteria will be in the egg salad?
256
Examples of Allopatric speciation
A population of ants are separated by a new, large housing development that prohibits gene flow.
Examples of Allopatric speciation
Abert's squirrels and Kaibab squirrels are two species that share a common ancestry but no longer interbreed because they are separated by the Grand Canyon.
Euryarchaeota ... Crenarchaeota
According to this phylogenetic tree, which of these pairs of prokaryotic subgroups share the most recent common ancestor?
mitochondrion
After a long period of coevolution, the aerobic bacterium consumed by the predatory cell became the cellular organelle known as the:
chloroplast
After a long period of coevolution, the photosynthetic bacterium consumed by the predatory cell became the cellular organelle known as the:
DNA
At some point, _____, a more stable molecule, became the genetic material.
Which structure helps bacteria to attach within the tissues that they will infect?
Capsule
gram-positive bacteria
Streptococcus aureus is classified with _____.
Which of the following examples uses the biological species concept to describe different species?
Female horses and male donkeys are able to mate, but their offspring (mules) are infertile.
polymers
The abiotic synthesis of ______ may have occurred as organic monomers splashed onto hot rocks and spontaneously joined into chains.
Behavioral isolation prevents different birds-of-paradise species from mating and reproducing. Which of the following describes a behavioral isolation reproductive barrier?
Males of one species perform orchestrated dances and sing songs that only attract females of the same species.
Gametic isolation
Many populations of clams release their sperm and eggs into the same region of a lake, but only the sperm and eggs from the same species successfully unite to form zygotes.
Example of Sympatric speciation
Medium size ground finches living on the same island develop different bill sizes, which alters their mating signals.
small organic molecules
The abiotic synthesis of ________ , such as amino acids and nitrogenous bases, may have occurred near volcanoes or around deep-sea vents.
the predatory cell is unable to digest the bacteria
The bacteria initially persist in the predatory cell because:
natural selection
Once some protocells contained self-replicating molecules, _________ could have begun to shape their properties as those that reproduced more efficiently would have increased in number.
chlamydias
Organisms that can cause nongonococcal urethritis are classified with _____.
Examples of Allopatric speciation
Pine forests separated by a mountain range, a canyon, or a body of water contain isolated populations of organisms.
Example of Sympatric speciation
Self-fertilization in plants allows a new species to arise amidst the ancestral population.
Example of Sympatric speciation
Small fish called cichlids live in the same lake but at different depths, which cues differential reproduction.
spirochetes
Spiral-shaped bacteria are likely to be placed with _____.
proteobacteria
The chemoheterotroph Proteus vulgaris is a rod-shaped bacterium classified with _____.
stromatolites
The earliest evidence of life on Earth is 3.5-billion-year-old fossils of ________ , which were built up by ancient photosynthetic prokaryotes.
protocells
The first _______ may have formed when collections of organic molecules became isolated within membranes.
RNA
The first genetic material was probably self-replicating _____.
speciation
The process that gives rise to new species is called
cyanobacteria
The prokaryotic cells that built stromatolites are classified as _____.
cyanobacteria
The prokaryotic cells that were the first to add significant quantities of oxygen to Earth's atmosphere are classified as _____.
Temporal isolation
Two populations of flowers do not produce offspring because one blooms during early spring and the other blooms during late spring.
Habitat isolation
Two populations of lobsters do not mate because one population lives in the Atlantic Ocean and the other lives in the Pacific Ocean.
colonization of land by plants
Which of these events occurred during the Paleozoic?
formation of oxygen
Which of these events occurred earliest in the history of Earth?
first humans
Which of these events occurred most recently in the history of Earth?
Morphological Species Concept
based on distinct body structures.
Biological Species Concept
based on reproductive isolation caused by prezygotic & postzygotic barriers.
biological species concept
defines a species as a group of populations whose members have the potential to interbreed with one another and produce fertile offspring.
Allopatric Speciation
in which gene flow is interrupted between geographically isolated populations.
Sympatric Speciation
in which gene flow is interrupted due to polyploidy, habitat differences, sexual selection.
reproductive barrier
is anything that prevents successful interbreeding between species.
Time
is shown along the X axis of a phylogenetic tree, with the most ancient time on the left, and the present day on the right.
phylogenetic tree
represents a species that is ancestral to all species to the right of that point. Thus, the far left point on this figure represents a species that is an ancestor of every species shown on the tree.
Hybrid Zones
which may results in fusion of species, stable hybrid zone, and reinforcement of reproductive barriers.