Dead Zones & Dissolved Oxygen
What organism rapidly increases in the Gulf when excess nutrients enter the water?
Answer: Phytoplankton
What is a producer?
Answer: An organism that makes its own food through photosynthesis
What is photosynthesis?
Answer: The process that uses sunlight, water, and carbon dioxide to make glucose and oxygen
What type of feedback loop makes a problem worse over time?
Answer: Positive feedback loop
What organelle is known as the “powerhouse of the cell”?
Answer: Mitochondria
200 — What process used by decomposers lowers dissolved oxygen in the Gulf?
Answer: Cellular respiration
200 — How does energy move through an ecosystem?
Answer: Sun → producers → consumers → decomposers
200 — What gas is released during photosynthesis?
Answer: Oxygen
200 — What would happen to shrimp populations, if oxygen levels dropped below 3mg/L?
Answer: Populations would die off, or migrate away as the water does not have enough oxygen for them to survive.
200 — What blood type is known as the universal donor?
Answer: O negative
300 — What are the two main ways oxygen enters ocean water?
Answer: Diffusion from the air and
photosynthesis
300 — How does matter move through ecosystems?
Answer: Matter cycles between organisms and the environment
300 — What gas is released during cellular respiration?
Answer: Carbon dioxide
300 — Why can warmer water worsen dead zones?
Answer: Warm water holds less dissolved oxygen
300 — How many bones are in the adult human body?
Answer: 206
400 — Why do fish and shrimp die or leave during hypoxic conditions?
Answer: They cannot get enough oxygen for cellular respiration
400 — What happens to phytoplankton populations when sunlight and nutrients increase in spring?
Answer: They rapidly increase
400 — What process do bacteria use while decomposing dead phytoplankton?
Answer: Cellular respiration
400 — Why can melting ice accelerate global warming?
Answer: Permafrost, stored carbon released, greenhouse effect
400 — What is the largest organ in the human body?
Answer: Skin
500 — Explain how fertilizer runoff can eventually create a dead zone.
Answer: Fertilizer increases phytoplankton growth; when phytoplankton die, bacteria decompose them and use oxygen during respiration, causing low dissolved oxygen
500 — Why is dissolved oxygen considered an indicator of ecosystem health in The Gulf of Mexico?
Answer: Most aquatic organisms need oxygen to survive
500 — Compare photosynthesis and cellular respiration.
Answer: Photosynthesis stores energy and removes carbon dioxide; respiration releases energy and produces carbon dioxide
500 — Historically, why is it important to peat, that colder temperatures affect decomposition and what role does solar radiation play?
Answer: 10,000 years ago, SR ^ vegetation, cold = stored peat/carbon
500 --- What percentage of Peat covers the world surface compared to the amount of carbon it stores in all the world’s forests combined?
Answer: 3% of land surface + twice as much CO2 stored