Mastering #4
The first animals evolved ________.
600 million years ago
The first animals evolved from ________.
Protists
Mollusks are more closely related to flatworms than to roundworms.
True
How do bony fish regulate buoyancy?
With an air-filled swim bladder
A population in ecology is defined as ________.
a group of organisms, all from the same species
Most of the prokaryotes known as ______ live in extreme environments, such as salty lakes.
archaea
Bacteria with rod-shaped cells connected end-to-end are called _________.
bacilli
Kingdom ______ consists of multicellular eukaryotes that produce their food by photosynthesis.
plantae
Genetically modified organisms that acquire genes from a different species are called ________ organisms.
transgenic
Binary fission produces __________.
two genetically identical bacterial cells Submit
For a species with a Type II curve, less than ____% of individuals survive for 50% of the maximum life span.
10
What is the difference between a community and an ecosystem?
A community includes interacting populations without their surrounding environment, while an ecosystem includes the surrounding environment. Submit
Why is it hard to classify protists? Because they differ in their complexity, some being unicellular, some being multicellular Because they come from such in such a wide variety of size and shape Because they differ in their nutrition and energy use All of the above are reasons why protists remain hard to classify
All of the above are reasons why protists remain hard to classify
Kingdom ________ consists of multicellular eukaryotes that obtain their food by ingesting (eating) other organisms.
Animalia
Serial repetition of segments is a defining characteristic of which worm phylum?
Annelids
What defines radial symmetry?
Any plane of symmetry passing through the center of the organism splits it into equal halves.
Which organisms are called extremophiles and flourish mostly in extreme conditions?
Archaea
Which worm phylum lacks body segmentation?
Both flatworms and roundworms
According to this graph, species that exhibit a Type III curve typically produce large numbers of offspring.
Cannot be determined from this graph
The echinoderms are most closely related to the ________.
Chordates
Which type of worm lacks a complete digestive tract?
Flatworms
Of those listed below, which category of classification is the most narrow?
Genus
What is represented on the x-axis of this graph?
Individuals' life spans as a percentage of the maximum life span for the species
What is the main difference between monotremes and eutherians?
Monotremes lay eggs, while eutherians give birth to live young.
What do sponges and cnidarians have in common? Mobility Symmetry Organization of cells into tissues None of the above are characteristics that sponges and cnidarians share
None of the above are characteristics that sponges and cnidarians share
For species with a Type III curve, most individuals reach the maximum life span.
Not supported
One of the features shared by all chordates is a(n)______, a flexible rod that runs along the top side of the back.
Notochord
Being a heterotroph means ________.
Obtaining your food by eating other organisms
What are the key characteristics of arthropods?
Segmented bodies, tough exoskeleton, and jointed appendages
Which specialized structures are unique to the cnidarians?
Stinging cells
In species that exhibit a Type II survivorship curve, individuals are no more likely to die at one stage of the life cycle than another.
Supported
At 50% of maximum life span, how does survivorship for a Type I curve compare to survivorship for a Type III curve?
Survivorship for a Type I curve is nearly 1,000 times as great as survivorship for a Type III curve.
According to this phylogenetic tree, which bear is most closely related to the American black bear?
The Asiatic black bear
Which of the following phyla is the most diverse and numerous of all animal phyla?
The arthropods
What do survivorship curves display?
The change that an individual will live to a particular age
Which of the following statement is correct regarding the phylogenetic tree above?
The polar bear and the brown bear are the most recently evolved species.
Which body form of the cnidarians is sessile?
The polyp
Three of the following statements are correct. Identify the statement that is not correct regarding genetically modified organisms. GM animals are not in our food supply. GM crops have been produced that are disease resistant. There are no risks associated with GM crops. GM crops have been produced with increased nutrition.
There are no risks associated with GM crops.
Which of the following best describes mollusks?
They are bilaterally symmetrical and have a soft body sometimes covered with a shell.
Why is a percentage scale used for the x-axis rather than actual ages?
This scale allows you to compare species with widely varying life spans on the same graph.
How did mitochondria and chloroplasts arise in eukaryotic cells?
Via endosymbiosis, where mitochondria and chloroplasts were independent prokaryotic organisms that were engulfed by a larger cell
_______ are the most diverse and widespread prokaryotes.
bacteria
Viruses that infect bacteria are called ________.
bacteriophages
The phylum _______ contains animals that share four specific anatomical features, including a hollow nerve cord and a tail.
chordate
Organisms with prokaryotic cells are separated into two _______, Bacteria and Archaea.
domains
All vertebrates have a(n) ________ , an internal system of bones (in your case, 206 bones).
endoskeleton
All organisms with eukaryotic cells are grouped in domain _______
eukarya
Kingdom ________ includes eukaryotic organisms that mostly decompose organic wastes and absorb nutrients into their cells.
fungi
A(n) ________ is an animal that lacks a backbone and may or may not have all of the chordate features.
invertebrate
A(n) _______ is an example of an animal that is a chordate but not a vertebrate.
lancelet
_______ are a diverse collection of mostly single-celled eukaryotes, which are sorted into several kingdoms to reflect their evolutionary relationships.
protists
A(n) ______ is an animal that has a backbone in addition to displaying the four features of all chordates.
vertebrate