Living Environment Regents High-Yield Study Flashcards

A comprehensive set of Q&A flashcards covering 21 high-yield biology topics for the Living Environment Regents exam, including homeostasis, genetics, ecology, and human impact.

What is the definition of homeostasis?

The maintenance of a stable internal environment (dynamic equilibrium) despite changing external conditions.

How do feedback loops regulate body temperature and blood sugar?

If body temperature rises, the body sweats to cool down. If blood sugar levels rise, the pancreas secretes insulin to lower them.

Why is high biodiversity essential for ecosystem stability?

High biodiversity allows ecosystems to better withstand environmental disasters, pest outbreaks, or climate shifts, and provides valuable medicine resources.

What are the three main stages of the DNA → mRNA → Protein pathway?

1. DNA stores genetic code in the nucleus; 2. Transcription copies DNA into mRNA; 3. Translation at the ribosome uses mRNA codons and tRNA to assemble amino acids into a protein.

What does the mnemonic RRR GENTS stand for in relation to life functions?

Regulation, Respiration, Reproduction, Growth, Excretion, Nutrition, Transport, and Synthesis.

Give an example of how body systems interact during exercise.

The Nervous system detects high $CO_2$, signaling the Respiratory system to breathe faster and the Circulatory system to pump oxygenated blood to muscles quicker.

What is an environmental trade-off?

A compromise involving a pros-and-cons situation where a technological solution has benefits (e.g., jobs) but also negative consequences (e.g., pollution).

What is gene regulation?

The process where environmental factors like temperature or light influence which genes are expressed without changing the actual DNA structure.

How is genetic variation produced in a population?

Through random mutations and sexual reproduction, which includes the sorting and recombination of genes.

How do enzymes function according to the "Lock and Key" model?

Enzymes are biological catalysts with a highly specific active site that fits only one specific substrate.

What happens to an enzyme if it is exposed to high temperatures or extreme pH values?

The enzyme will denature, meaning it loses its shape and stops working.

What is an example of biological structure being related to function?

Red blood cells are smooth and flexible to squeeze through narrow capillaries, and the cell membrane is semi-permeable to regulate what enters/exits.

What is the difference between Mitosis and Meiosis?

Mitosis creates $2$ identical diploid ($2n$) body cells for growth and repair, while Meiosis creates $4$ genetically unique haploid ($n$) gametes for reproduction.

What is the process of cell differentiation?

The process where identical embryonic stem cells activate different segments of their DNA to become specialized tissues like nerve, muscle, or skin.

What is the pathway of development following fertilization?

Zygote → Mitosis (Cleavage) → Embryo → Differentiation.

What is the function of the placenta during fetal development?

It allows nutrients and wastes to cross between the mother and fetus without blending their blood lines.

What is the chemical formula for Photosynthesis?

$$\text{Water} + \text{Carbon Dioxide} + \text{Light} \rightarrow \text{Glucose} + \text{Oxygen}$$

Match the organic polymers to their building blocks (monomers).

Glucose/Simple Sugars → Starch; Amino Acids → Proteins; Nucleotides → DNA/RNA; Fatty Acids & Glycerol → Lipids.

What is the chemical formula for Cell Respiration?

$$\text{Glucose} + \text{Oxygen} \rightarrow \text{ATP (Energy)} + \text{Water} + \text{Carbon Dioxide}$$

What determines the carrying capacity of an ecosystem?

Limiting factors such as food, water, predators, disease, and nesting space.

How does fertilizer runoff impact aquatic environments?

It causes industrial pollution known as eutrophication, which leads to algae blooms that suffocate aquatic life.

What is the 10% Rule in ecosystem energy flow?

Only about $10\%$ of energy moves to the next trophic level; the remaining $90\%$ is lost as metabolic heat.

How does the Carbon Cycle balance atmospheric $CO_2$?

Photosynthesis pulls $CO_2$ out of the atmosphere, while Cell Respiration, Combustion, and Decomposers return it.

What are the components of Charles Darwin's Natural Selection process?

Overproduction → Competition → Genetic Variation → Survival of the Fittest → Reproduction.

What is the difference between the Biosphere and the Geosphere?

The Biosphere consists of all living components (plants, animals, microbes), while the Geosphere consists of non-living structural features (rocks, soil, mountains).

Differentiate between quantitative and qualitative data.

Quantitative data are measurable or numerical recordings (e.g., $5.4\,\text{cm}$), while qualitative data are descriptive observations of sensory properties (e.g., "fuzzy" or "amber").