PCB 3044
PCB 3044 Exam 3 Questions with
Correct Answers 2026
Chapter 12: Predation
Hudson Bay Co. Trade
Allows us to track population cycles of snowshoe hares
What causes population cycles in hare and lynx?
-FOOD supplies become limiting when hare population density is high
- PREDATION by lynx and other predators can explain drop in survival rates
Predation
a trophic interaction where individuals of one species (a predator) benefits by
consuming individuals of another species (its prey).
Parasitoids
insects that lay eggs within another host, after hatching the larvae stay in the
host which they eventually kill and eat
Predators generally focus on areas that
yield abundant prey
(Some predators are sit and wait, while others relocate to areas with abundant
prey)
Generalist Predators
Most Predators are often generalists and consume whatever is available
Specialist Predators
show a preference in what they eat regardless of abundance
(ex. Hare constitute 20% of lynx available food, yet make-up 60-80% of their
diet)
Search image:
PCB 3044
,PCB 3044
the heightened ability of a predator to detect a target
(Animals will gain experience with specific species of prey to become more
efficient at capturing them
This will lead the predator to focus on that species and ignore other prey)
Herbivores eat
they are mostly specialists and eat specific parts of plants
(Leaves are the most consumed part; other than seeds because of their
abundance and nutrition)
Nitrogen content from greatest to least
-animals
-seeds
-angiosperm leaves
-gymnosperm leaves
-phloem sap
-xylem sap
Herbivores reduce what?
Herbivores reduce the growth, survival, and reproduction of plants
(Seed consumption limits reproductive success
Growth is reduced after herbivory (eating)of roots)
Narrow range
Herbivores feed on a narrow range of plants.
(grass hoppers feed on a wide range)
How do predators forage for food?
some search through their habitat (wolves)
some sit and wait for prey to enter their striking zone(sessile, like carnivorous
plants)
For any prey defense mechanism
there is usually a predator with a countervailing offense
Many predator have physical features
PCB 3044
, PCB 3044
for prey capture
(snake skull bones aren't rigid so they can eat bigger things than their heads)
Poison and mimicry
Some predators use poison to subdue prey (venomous spiders), others use
mimicry to blend into their surroundings
Tolerate chemicals
Other predators can tolerate or detoxify chemicals from the prey (Garter snakes
can eat toxic newts, but they move slower and are stationary for 7 hour after
eating them)(they have an evolved resistance to the toxin)
Prey defenses (to escape being eaten by predators)
large size (elephants)
rapid movement (gazelles)
body armor (snails, armadillo)
Coloration defense mechanisms used by prey
Aposematic- warns predators not to eat toxic organisms (based on bright colors)
Crypsis- helps prey resemble their background and blend in (camouflage)
False advertising- coloring that resembles other toxic/ dangerous organisms (but
the animal itself isn't toxic)
Mimicry defense mechanism
when prey resembles another fierce organism or the environment
Batesian- 1 species mimics a different harmful species
Mullerian- both species are harmful
Prey alter their behavior
by avoiding open area
keeping a lookout
and forming defensive circles
Some prey have chemical
repellents that are toxic or irritating, with varying levels of accuracy
-All adaptations have trade offs
(ex. Of 4 snail species eaten by shore crabs, the species with the thinnest shell
takes refuge most quickly. Snails with thickest shells are the last to take refuge.)
PCB 3044
PCB 3044 Exam 3 Questions with
Correct Answers 2026
Chapter 12: Predation
Hudson Bay Co. Trade
Allows us to track population cycles of snowshoe hares
What causes population cycles in hare and lynx?
-FOOD supplies become limiting when hare population density is high
- PREDATION by lynx and other predators can explain drop in survival rates
Predation
a trophic interaction where individuals of one species (a predator) benefits by
consuming individuals of another species (its prey).
Parasitoids
insects that lay eggs within another host, after hatching the larvae stay in the
host which they eventually kill and eat
Predators generally focus on areas that
yield abundant prey
(Some predators are sit and wait, while others relocate to areas with abundant
prey)
Generalist Predators
Most Predators are often generalists and consume whatever is available
Specialist Predators
show a preference in what they eat regardless of abundance
(ex. Hare constitute 20% of lynx available food, yet make-up 60-80% of their
diet)
Search image:
PCB 3044
,PCB 3044
the heightened ability of a predator to detect a target
(Animals will gain experience with specific species of prey to become more
efficient at capturing them
This will lead the predator to focus on that species and ignore other prey)
Herbivores eat
they are mostly specialists and eat specific parts of plants
(Leaves are the most consumed part; other than seeds because of their
abundance and nutrition)
Nitrogen content from greatest to least
-animals
-seeds
-angiosperm leaves
-gymnosperm leaves
-phloem sap
-xylem sap
Herbivores reduce what?
Herbivores reduce the growth, survival, and reproduction of plants
(Seed consumption limits reproductive success
Growth is reduced after herbivory (eating)of roots)
Narrow range
Herbivores feed on a narrow range of plants.
(grass hoppers feed on a wide range)
How do predators forage for food?
some search through their habitat (wolves)
some sit and wait for prey to enter their striking zone(sessile, like carnivorous
plants)
For any prey defense mechanism
there is usually a predator with a countervailing offense
Many predator have physical features
PCB 3044
, PCB 3044
for prey capture
(snake skull bones aren't rigid so they can eat bigger things than their heads)
Poison and mimicry
Some predators use poison to subdue prey (venomous spiders), others use
mimicry to blend into their surroundings
Tolerate chemicals
Other predators can tolerate or detoxify chemicals from the prey (Garter snakes
can eat toxic newts, but they move slower and are stationary for 7 hour after
eating them)(they have an evolved resistance to the toxin)
Prey defenses (to escape being eaten by predators)
large size (elephants)
rapid movement (gazelles)
body armor (snails, armadillo)
Coloration defense mechanisms used by prey
Aposematic- warns predators not to eat toxic organisms (based on bright colors)
Crypsis- helps prey resemble their background and blend in (camouflage)
False advertising- coloring that resembles other toxic/ dangerous organisms (but
the animal itself isn't toxic)
Mimicry defense mechanism
when prey resembles another fierce organism or the environment
Batesian- 1 species mimics a different harmful species
Mullerian- both species are harmful
Prey alter their behavior
by avoiding open area
keeping a lookout
and forming defensive circles
Some prey have chemical
repellents that are toxic or irritating, with varying levels of accuracy
-All adaptations have trade offs
(ex. Of 4 snail species eaten by shore crabs, the species with the thinnest shell
takes refuge most quickly. Snails with thickest shells are the last to take refuge.)
PCB 3044
