Cladograms
On a cladogram, this point represents where one ancestral lineage splits into two descendant lineages.
node
This field of biology involves identifying, naming, and classifying organisms.
taxonomy
In the food chain grass → rabbit → snake → hawk, which trophic level does the rabbit represent?
primary consumer
A deer obtains energy almost entirely by consuming leaves, grasses, and other plant tissues. Which category of consumer describes it?
herbivore
Two male deer attempt to gain access to the same limited territory and mates. Which ecological relationship is occurring in this scenario?
competition
On a cladogram, each node represents a(n) ___.
common ancestor
Canis lupus and Canis latrans demonstrate this standardized two-part system for scientifically naming organisms.
binomial nomenclature
In the food chain algae → zooplankton → minnow → bass, which trophic level does the minnow represent?
secondary consumer
An organism cannot manufacture its own food and must obtain energy from other organisms or organic matter. Which broad category describes this organism?
heterotroph
An owl captures, kills, and consumes a mouse. Which ecological relationship exists between these two organisms?
predation
A characteristic appears on a cladogram AFTER Species A branches off, but BEFORE Species B and C separate. Which species should display that characteristic? (A, B, and/or C?)
Scientists analyze DNA evidence and determine that two organisms previously placed in different groups actually share a more recent common ancestor than expected. They create a branching diagram to represent their revised evolutionary relationships. What is the diagram called? (Hint: NOT a cladogram)
phylogenetic tree
An ecosystem contains plants, herbivorous insects, insect-eating frogs, and snakes that eat those frogs. To which trophic level do the snakes belong?
tertiary consumer
A bear eats berries, roots, insects, fish, and small mammals. Based specifically on its food sources, which category describes it?
omnivore
A tick feeds on a mammal's blood, gaining nutrients while reducing the mammal's fitness. Which ecological relationship is being demonstrated in this scenario?
parasitism
On a cladogram, Species A and B share a common ancestor at one node. Species B and C share a common ancestor at a more recent node. To which species is Species B more closely related?
Species C
Kingdom, phylum, class, order, family, genus, and species are the major ranks used in which classification system?
Linnaean classification
A food chain contains four trophic levels. An organism receives energy by eating an organism occupying the third trophic level. Which trophic level does this organism represent?
tertiary consumer
An organism captures energy from sunlight and uses inorganic materials to produce its own food. Which category describes this organism?
autotroph
Barnacles attach to a whale and gain transportation to food-rich waters, while the whale experiences no significant benefit nor harm. Which symbiotic relationship is demonstrated by this scenario?
commensalism
On a cladogram, Species A branches off before a new characteristic appears. Species B branches off after that characteristic appears, and Species C and D branch off even later after that characteristic appears. Which species would be expected to display the characteristic?
Species B, C, and D
Two scientists studying the same organism call it a "mountain lion" and a "cougar", creating confusion because common names vary. Which classification practice solves this problem by giving the organism one standardized two-part scientific name?
binomial nomenclature
After organisms at several trophic levels die, fungi and bacteria break down their remains and return their nutrients to the ecosystem. What ecological role do these fungi and bacteria fill?
decomposer
Two organisms are both heterotrophs. Organism A obtains energy exclusively by consuming other animals. Organism B consumes both producers and consumers. Give the most specific consumer category for each organism.
Organism A is a carnivore. Organism B is an omnivore.
Bacteria living within an animal's digestive tract receive nutrients and shelter, while producing compounds that benefit the animal. Which type of symbiotic relationship is occurring in this scenario?
mutualism