CA QAL/QAC CATEGORY F (AQUATIC) HIGH-QUALITY EXAM QUESTIONS AND VERIFIED ANSWERS

1. What is the primary producer in most aquatic ecosystems?
o A) Fish
o B) Zooplankton
o C) Phytoplankton
o D) Bacteria ANSWER : C) Phytoplankton
2. Which zone of a lake receives sufficient sunlight for photosynthesis?
o A) Benthic zone
o B) Profundal zone
o C) Euphotic zone
o D) Abyssal zone ANSWER : C) Euphotic zone
3. What is eutrophication?
o A) Water becoming more acidic
o B) Excessive nutrient enrichment leading to algae blooms
o C) Decrease in water temperature
o D) Increase in water salinity ANSWER : B) Excessive nutrient
enrichment leading to algae blooms
4. Which aquatic plant is completely submerged and rooted?
o A) Water hyacinth
o B) Coontail

, o C) Cattails
o D) Water lilies ANSWER : B) Coontail
5. What are emergent aquatic plants?
o A) Plants that float on the surface
o B) Plants rooted in sediment with stems/leaves above water
o C) Completely submerged plants
o D) Plants with floating leaves only ANSWER : B) Plants rooted
in sediment with stems/leaves above water
6. Which organism is an example of zooplankton?
o A) Daphnia
o B) Algae
o C) Coontail
o D) Duckweed ANSWER : A) Daphnia
7. What is the thermocline in a lake?
o A) The surface layer
o B) The bottom layer
o C) The layer of rapid temperature change
o D) The area with highest oxygen ANSWER : C) The layer of
rapid temperature change
8. Which factor most influences dissolved oxygen levels in water?
o A) Water color
o B) Temperature and photosynthesis
o C) Soil type
o D) Moon phase ANSWER : B) Temperature and
photosynthesis
9. What is the littoral zone?
o A) Deep water area
o B) Shallow water area near shore where light penetrates

, o C) Open water surface
o D) Underground water source ANSWER : B) Shallow water
area near shore where light penetrates
10.Which invasive aquatic plant spreads primarily by fragmentation?
o A) Hydrilla
o B) Cattails
o C) Bulrush
o D) Native pondweed ANSWER : A) Hydrilla
11.What is the primary concern with excessive aquatic vegetation?
o A) Improved water clarity
o B) Oxygen depletion, impeded water flow, and recreation
interference
o C) Increased fish populations
o D) Better erosion control ANSWER : B) Oxygen depletion,
impeded water flow, and recreation interference
12.Which aquatic plant classification includes water hyacinth?
o A) Submersed
o B) Emergent
o C) Free-floating
o D) Rooted-floating ANSWER : C) Free-floating
13.What pH range is considered neutral in aquatic systems?
o A) 4-5
o B) 6-7
o C) 7-8
o D) 9-10 ANSWER : C) 7-8
14.Which condition indicates poor water quality?
o A) High dissolved oxygen
o B) Clear water

, o C) Low dissolved oxygen and high turbidity
o D) Presence of native fish ANSWER : C) Low dissolved oxygen
and high turbidity
15.What are benthic organisms?
o A) Organisms living on or in bottom sediments
o B) Floating organisms
o C) Flying insects only
o D) Fish in open water ANSWER : A) Organisms living on or in
bottom sediments
16.Which nutrient is most commonly associated with algae blooms?
o A) Iron
o B) Phosphorus
o C) Sodium
o D) Calcium ANSWER : B) Phosphorus
17.What is stratification in a lake?
o A) Uniform temperature throughout
o B) Distinct temperature layers
o C) Ice formation
o D) Sediment settling ANSWER : B) Distinct temperature layers
18.Which aquatic plant has both underwater and floating leaves?
o A) Elodea
o B) Water lily
o C) Duckweed
o D) Coontail ANSWER : B) Water lily
19.What is turbidity?
o A) Water temperature
o B) Water clarity or cloudiness
o C) Water salinity