Life Science: Biology – Regents Review Flashcards (June ’25 notes)

A set of practice QA flashcards covering key concepts from the Life Science: Biology Regents notes, including ecology, physiology, evolution, genetics, and human health topics.

Which claim about the kelp carbon pool is best supported by the information and the model (with and without sea otters) you studied?

The carbon storage is higher with the otters present because sea otters eat sea urchins, reducing kelp destruction and allowing more kelp carbon to be stored.

In the kelp–otter–sea urchin model, where does some of the carbon from dead kelp end up due to low oxygen on the sea floor?

In the geosphere (sediments on the sea floor) where decomposition is slow.

Which process converts light energy into chemical energy in kelp?

Photosynthesis.

Which trend is shown by the graph relating atmospheric CO2 concentration and seawater pH?

As atmospheric CO2 increases, seawater pH decreases (ocean acidification).

Which marine organisms are affected by lower seawater pH as CO2 rises?

Corals, mussels, plankton, seastars, and sea urchins.

What is the chemical reaction model that describes the formation of calcium carbonate shells in sea urchins?

Ca2+ + CO3^2− → CaCO3 (calcification).

Where does carbon in living kelp primarily come from and go when kelp dies and sinks to the sea floor?

Kelp takes in carbon via photosynthesis; upon death, carbon can be stored as biomass in kelp or become part of the deep-sea carbon pool in low-oxygen sediments.

Which statement describes how the model helps explain carbon entering the atmosphere being reduced by kelp activity?

Some carbon stored in dead kelp is trapped in the geosphere on the sea floor, reducing atmospheric carbon.

What process is identified in the model as converting light energy into chemical energy inside kelp?

Photosynthesis.

Which statement about ocean acidification and carbonate availability is true?

Increased CO2 lowers pH and decreases the availability of carbonate ions needed for shells and skeletons.

Which organ produces erythropoietin (EPO), which stimulates red blood cell production?

The kidneys.

What triggers the production of EPO in the body?

Low oxygen levels (hypoxia).

What is the function of aquaporins on red blood cells?

They facilitate the transport of water across the cell membrane, aiding in osmoregulation.

How does water uptake affect red blood cell membrane flexibility and oxygen transfer capacity according to the graph?

Water uptake increases membrane flexibility and increases the rate of oxygen transfer.

Which question best identifies whether a leg deformity in frogs could be inherited?

Is a mutation that causes abnormal legs present in the DNA of the sex cells of the parents?

Which parasite is responsible for frog limb deformities through its life cycle?

Ribeiroia.

Which outcome best supports the claim that Ribeiroia deformities enhance parasite survival and reproduction?

The most severely deformed frogs are more likely to be eaten by birds, allowing Ribeiroia to complete its life cycle.

How do Ribeiroia parasites influence limb development via retinoic acid and Hox genes?

Parasites increase retinoic acid, which influences Hox gene activity and limb formation.

Which statement best explains how retinoic acid levels influence the growth of extra limbs in tadpoles?

Increased retinoic acid levels activate limb formation genes via Hox gene regulation.

Which question could address whether retinoic acid levels influence inheritance of limb development traits?

Do retinoic acid levels affect inheritance of Hox gene regulation for limb development?

What evidence supports that arthropods share a common ancestor based on Hox genes?

Similar patterns of Hox gene activity that control body segmentation across different arthropods.

If specific Hox genes from a mouse and a fruit fly are interchanged, why might typical eyes still develop in both species?

Because Hox genes have conserved regulatory roles in development; swapped genes can still activate eye-development pathways.

Which adaptation helps yaks survive at high altitude with low oxygen?

A large heart and lungs and a specialized hemoglobin that extracts more oxygen from the air.

What is the most likely origin of the EPAS1 allele that increases yak hemoglobin?

A change in the EPAS1 gene sequence that occurred during meiosis in yak germ cells (heritable variation).

What behavioral adaptation is expected for pikas to survive the Tibetan Plateau’s climate, based on altitude-related temperature data?

Burrowing to provide shelter and conserve heat, along with potential food caching and stamina to forage in cold conditions.

Based on the biomass pyramid for the Tibetan Plateau ecosystem, what general trend is observed as energy moves up trophic levels?

Biomass decreases from producers to higher trophic levels, indicating energy transfer efficiency is low.

Which factor would have the greatest immediate effect on the low salt marsh population of smooth cordgrass after a severe storm?

Temporary increase in salinity and/or erosion disrupting the moist soil and habitat.

What claim about sea level rise and low marsh organisms can be evaluated using NASA’s sea-level data?

Rising sea levels will impact the numbers and types of organisms interacting in a low marsh by altering habitat and salinity regimes.

Which restoration option best promotes a stable, interactive salt marsh ecosystem?

Planting vegetation along damaged shorelines to restore habitat structure and shelter.

Which statement best describes how natural shoreline erosion and habitat carrying capacity interact at vegetation-rich shores?

Erosion without vegetation can rapidly decrease habitat carrying capacity; vegetation buffers and moderates this effect.

Which intervention would most likely minimize erosion while preserving habitat complexity at a shoreline?

Living shoreline options (vegetation-based approaches) are preferred over hard structures for ecological stability.

In assessing prairie dog–burrowing owl interactions, how does changing prairie dog burrow availability affect owls?

As burrows decrease, burrowing owl carrying capacity generally decreases; owl populations depend on prairie dogs for habitat.

Which evidence would support that DNA carries inherited information influencing birth weight from famine-exposed mothers to their children?

Whether birth weight-related genes are present in the DNA of both parents (heritable).

In the IGF2 sequence, if a codon changes from GAG (glutamic acid) to GAC (aspartic acid), what is the consequence for the protein?

The protein would incorporate aspartic acid instead of glutamic acid at that position.

What is the effect of unmethylated DNA on IGF2 expression and fetal growth?

Unmethylated DNA usually increases gene expression, which can lead to greater IGF2 activity and increased fetal growth.

What does evidence that offspring show similar health problems despite lack of famine exposure suggest about DNA methylation?

DNA methylation patterns can be inherited across generations, affecting gene expression.

How does demethylation influence lung cell tumor progression, according to the model?

Demethylation removes silencing and increases expression of genes that promote cell division, aiding tumor progression.

What type of treatment could potentially decrease tumor growth by modifying methylation?

A treatment that adds methyl groups to genes associated with increased cell division (methylation therapies).