Overview
This Regents Living Environment exam covers key biology concepts such as cell structure and function, genetics, evolution, ecology, human impact on the environment, and experimental design, using both multiple-choice and open-ended questions.
Cell Structure and Function
- DNA in neighboring cells directs skin repair via mitotic division.
- ATP is produced in the mitochondria.
- Ribosomes are the site of protein synthesis in cells.
- Cell membranes are vital for gas exchange, such as oxygen intake in ameba.
Genetics and Evolution
- Changing gene frequencies in a population leads to biological evolution.
- Mutations in reproductive cells (e.g., caused by UV radiation) can affect future plant generations.
- Selective breeding can reduce genetic diversity.
- Epigenetics alters gene expression without changing DNA sequences; environmental factors like diet influence it.
- Mitochondria are inherited maternally and are essential for energy production in complex organisms.
Ecology and Energy Flow
- Trees releasing toxins into soil reduce competition for nutrients, water, and sunlight.
- Removal/introduction of species (e.g., wolves or mongooses) can destabilize ecosystems.
- Producers, consumers, and decomposers form the correct energy flow sequence in ecosystems.
- Stored energy in food webs decreases up trophic levels due to loss as heat.
- Biodiversity increases ecosystem stability.
Human Impact and Environmental Issues
- Recycling and repairing reduce depletion of finite resources.
- Stratospheric aerosol scattering may help mitigate climate change but does not address emissions.
- Chemical pollution accumulates up food chains, especially in top predators.
- Habitat restoration (e.g., moving grazing animals) can restore environmental stability.
- Human actions like overharvesting plants can drive natural selection and reduce biodiversity.
Reproduction and Development
- Female cats are spayed by removing ovaries and uterus, preventing reproduction.
- Proper function of gametes (e.g., sperm's tail and nucleus) is vital for fertilization.
- Blockage of reproductive structures can prevent zygote formation.
- Uterus is essential for embryo development; transplants require immunosuppression.
Experimental Design and Data Analysis
- Science experiments require hypothesis testing and data collection.
- Averaging multiple readings increases accuracy (e.g., for pulse rate).
- Biochemical tests like gel electrophoresis and enzyme activity aid in determining genetic relationships.
Adaptations and Natural Selection
- Species with more surviving offspring have evolutionary advantages.
- Phenotypes (e.g., flower color, finch beak) influenced by environment and selective pressures.
- Shared behaviors or structures (e.g., egg positions in birds and dinosaurs) indicate common ancestry.
- Differences in traits among identical twins can be due to epigenetic changes.
Key Terms & Definitions
- Mitosis — type of cell division for growth and repair.
- ATP — main energy-carrying molecule in cells.
- Mutation — change in DNA sequence.
- Epigenetics — inheritable gene expression changes without DNA sequence alteration.
- Keystone species — species critical to maintaining ecosystem stability.
- Producers/Consumers/Decomposers — organisms at different food web levels.
- Biodiversity — variety of species in an ecosystem.
- Abiotic factors — non-living environmental components (e.g., water, nitrogen).
Action Items / Next Steps
- Review answer sheets for completeness and accuracy.
- Study diagrams related to food webs, energy pyramids, and reproductive anatomy.
- Complete any assigned graphing or data analysis tasks.
- Practice explaining biological processes using specific examples from the exam.