Zool 250 Exam Questions and Answers with Verified Solutions |
Latest 2026 Update
Q: What classifies an animal?
Answer:
Mobile at some point No cell wall (extracellular matrix)
Ingestive heterotrophs Multicellular
Q: Why are invertebrates important?
Answer:
Major part of food web Genetic studies/model organisms
Biodiversity Ecological roles Agriculture Evolutionary history
Q: What group makes up the largest amount of species?
Answer:
Invertebrates
Q: What group makes the smallest yet most studied group of species?
Answer:
Chordates
Q: What do vertebrate and invertebrate species graphs look like?
Answer:
Vertebrate species plateau, while invertebrates have linear increasing species
Q: How much of invertebrate species are "undescribed"?
Answer:
More than 50%
Q: Whats the most abundant invertebrate?
Answer:
Nematodes
Q: What mode is most biomass in?
Answer:
Aquatic
,Q: How are invertebrates used in medicine?
Answer:
Disease
Pathogens and vectors of pathogens Models for the study of disease
Genetic homology
Drug discovery and production Surgical aids
Q: How are invertebrates used in economics?
Answer:
Food production
Agriculture
Eating invertebrates and their products Pests
Food crops, lumber, livestock, pets Production of non-food commodities
Silk, pearls, dyes Technology
Biomimicry, materials
Using species as a model or solution for technological problems
Q: What is miniaturization?
Answer:
The trend of invertebrates having smaller body plans
Q: How are invertebrates used in science?
Answer:
Genetic and developmental model organisms
Fruit flies, round worms/nematode Occupy a wide range of ecological niches
Morphological and functional diversity Important to ecosystems
Ancient evolutionary history
Q: How is biomass distributed between invertebrates and vertebrates?
Answer:
Small "size" requirements facilitate observation and study
0 0 Invertebrates have a large number of species but have a small individual
biomass
Vertebrates have less species but large individual biomass
, Q: How do invertebrates affect conservation?
Answer:
Biodiversity loss
Utilitarian opportunity costs and ethical tragedy
Losing useful species Invasive species
Invertebrates are not immune to being invasive Biological control
Natural enemies of pest species
Introduce predators to get rid of pests
Q: Where do invertebrates live?
Answer:
Everywhere
Terrestrial, aquatic, interstitial, parasitic
Q: What are considerations in invertebrate gas exchange in water vs air?
Answer:
Surfaces must be moist
Aquatic inverts can use most body surfaces
Particularly when small and thin
Specialized respiratory structures needed for terrestrial inverts
Q: What are considerations in invertebrate fertilization in water vs air?
Answer:
- Aquatic organisms can use external fertilization
No specialized behaviours for mating
Terrestrial generally use internal fertilization, or return to water to breed
Q: What are considerations in invertebrate waste excretion in water vs air?
Answer:
Ammonia is a metabolic product that is toxic
Aquatic organisms can dilute their ammonia to avoid poisoning themselves
0 0 Terrestrial organisms could do this as well, but water is not readily available,
and all the water would be poisoned with ammonia
--> Specialized physiology is required to excrete ammonia products
Latest 2026 Update
Q: What classifies an animal?
Answer:
Mobile at some point No cell wall (extracellular matrix)
Ingestive heterotrophs Multicellular
Q: Why are invertebrates important?
Answer:
Major part of food web Genetic studies/model organisms
Biodiversity Ecological roles Agriculture Evolutionary history
Q: What group makes up the largest amount of species?
Answer:
Invertebrates
Q: What group makes the smallest yet most studied group of species?
Answer:
Chordates
Q: What do vertebrate and invertebrate species graphs look like?
Answer:
Vertebrate species plateau, while invertebrates have linear increasing species
Q: How much of invertebrate species are "undescribed"?
Answer:
More than 50%
Q: Whats the most abundant invertebrate?
Answer:
Nematodes
Q: What mode is most biomass in?
Answer:
Aquatic
,Q: How are invertebrates used in medicine?
Answer:
Disease
Pathogens and vectors of pathogens Models for the study of disease
Genetic homology
Drug discovery and production Surgical aids
Q: How are invertebrates used in economics?
Answer:
Food production
Agriculture
Eating invertebrates and their products Pests
Food crops, lumber, livestock, pets Production of non-food commodities
Silk, pearls, dyes Technology
Biomimicry, materials
Using species as a model or solution for technological problems
Q: What is miniaturization?
Answer:
The trend of invertebrates having smaller body plans
Q: How are invertebrates used in science?
Answer:
Genetic and developmental model organisms
Fruit flies, round worms/nematode Occupy a wide range of ecological niches
Morphological and functional diversity Important to ecosystems
Ancient evolutionary history
Q: How is biomass distributed between invertebrates and vertebrates?
Answer:
Small "size" requirements facilitate observation and study
0 0 Invertebrates have a large number of species but have a small individual
biomass
Vertebrates have less species but large individual biomass
, Q: How do invertebrates affect conservation?
Answer:
Biodiversity loss
Utilitarian opportunity costs and ethical tragedy
Losing useful species Invasive species
Invertebrates are not immune to being invasive Biological control
Natural enemies of pest species
Introduce predators to get rid of pests
Q: Where do invertebrates live?
Answer:
Everywhere
Terrestrial, aquatic, interstitial, parasitic
Q: What are considerations in invertebrate gas exchange in water vs air?
Answer:
Surfaces must be moist
Aquatic inverts can use most body surfaces
Particularly when small and thin
Specialized respiratory structures needed for terrestrial inverts
Q: What are considerations in invertebrate fertilization in water vs air?
Answer:
- Aquatic organisms can use external fertilization
No specialized behaviours for mating
Terrestrial generally use internal fertilization, or return to water to breed
Q: What are considerations in invertebrate waste excretion in water vs air?
Answer:
Ammonia is a metabolic product that is toxic
Aquatic organisms can dilute their ammonia to avoid poisoning themselves
0 0 Terrestrial organisms could do this as well, but water is not readily available,
and all the water would be poisoned with ammonia
--> Specialized physiology is required to excrete ammonia products
