Regents Biology Review

Introduction

• Purpose: To help students prepare for the Regents Living Environment Exam (New York State).
• Content: Focus on biology knowledge rather than laboratory skills.
• Exam Structure: Four-part exam including multiple choice and open-ended questions.

Key Ideas Overview

• Key Ideas 1-3: Covers about half of the biology content needed for the exam.

Levels of Organization in Life

• Population: A group of organisms of one species in one location.
• Trophic Levels:
  • Producers (autotrophs): Generate their own food (e.g., plants).
  • Consumers (heterotrophs): Consume producers.
  • Decomposers: Break down organic material.
• Food Web vs. Food Chain:
  • Food web: Interconnected food chains within an ecosystem.
  • Energy Pyramid: Energy loss (up to 90%) at each trophic level.

Ecosystem Dynamics

• Biotic and Abiotic Factors: Interactions shape ecosystems.
• Carrying Capacity: Maximum population an environment can sustain due to resource limits.
• Population Stability: Achieved through natural checks in the ecosystem.

Human Biology

• Complexity:
  • Molecules -> Cells -> Tissues -> Organs -> Organ Systems.
  • Systems include digestive, circulatory, respiratory, etc.
• Homeostasis: Maintaining stable internal conditions (e.g., sweating, shivering).

Cell Structure and Function

• Specialization: Cells with organelles performing specific functions.
• Organelles: Mitochondria (energy), ribosomes (protein synthesis), nucleus (DNA storage), vacuole (storage).
• Cell Types:
  • Eukaryotic: Complex, membrane-bound organelles, DNA in nucleus.
  • Prokaryotic: Simple, no membrane-bound organelles, DNA not in nucleus.

DNA and Protein Synthesis

• DNA Structure:
  • Double helix, base pairs A-T, G-C.
  • DNA -> RNA (transcription) -> Protein (translation).
• Protein Synthesis:
  • DNA determines protein sequence.
  • Proteins made of amino acids.

Genetic Engineering and Biotechnology

• Tools: Gel electrophoresis for DNA analysis (e.g., crime scene investigation).
• Transgenic Organisms: Genetic modification for agriculture, industry.
• Evolutionary Relationships: Using DNA to study evolutionary links.

Evolution

• Mutation and Variation:
  • Mutations: Changes in DNA sequence can lead to new traits.
  • Natural selection: Survival of the fittest.
• Adaptations: Behavioral, structural, reproductive adaptations for survival.
• Phylogenetic Trees: Diagrams showing evolutionary relationships.
• Extinction: Species can become extinct if not adaptable.

Conclusion

• Exam Review: Follow-up videos to cover remaining curriculum topics.
• Additional Resources: Use linked resources for further study.