Core Concepts in Biology, Ecology, and Geology

Posted on Apr 30, 2025 in Biology

Ecology & Environment Concepts

Biotope

The non-living components within an ecosystem.

Symbiosis

A close and long-term interaction between two different biological species. Note: The original definition described a specific type, likely obligatory mutualism.

Mutualism

A relationship between individuals of different species where both individuals benefit.

Population

A group of individuals of the same species that share the same habitat.

Decomposers

Organisms that break down dead organic matter, turning it into inorganic substances.

Phototropism

The movement or growth of plants in response to light.

Adaptations

Morphological Adaptation

Adaptation related to the form or structure of an organism.

Physiological Adaptation

Adaptation related to body functions, such as hibernation or lethargy.

Geology & Resources

Properties of Minerals

  • Luster (Brightness)
  • Color
  • Hardness
  • Toughness
  • Cleavage/Exfoliation

Rock Definition

An inert, solid substance (excluding petroleum) composed of one or more minerals. The most abundant rock in Santa Catarina is granite.

Uses of Rocks

  1. Energy conservation (e.g., insulation)
  2. Building materials

Origin of Oil (Petroleum)

Formed from the remains of microscopic marine plants and animals. It is found in underground deposits, and complex facilities are required for its extraction.

Origin of Coal

Formed from the accumulation, burial, and compression of large masses of plant matter over geological time.

Pollution from Oil Use

Major pollution problems arising from the use of oil as energy include:

  • Combustion releases substances that heavily contaminate the atmosphere.
  • Transportation can lead to accidents causing serious damage to marine environments.
  • Extraction processes produce a significant impact on the landscape.

Soil Definition

The superficial layer of the earth’s crust where vegetation grows, plants anchor their roots, and small animals live. Soil is composed of mineral matter, organic matter, air, and water.

Soil Formation Factors

Factors influencing soil formation and evolution include:

  • Parent Material (Bedrock providing initial materials)
  • Climate
  • Vegetation
  • Topography (Relief)
  • Time

Biochemistry Essentials

Role of Carbohydrates

Also called saccharides or carbs; primary functions include providing energy and structural support.

Role of Lipids

Functions include energy storage, structural components of cell membranes, and signaling.

Role of Proteins

Functions include structural support, transport of substances, enzymatic activity, and defense mechanisms.

Role of Water

Essential for life, serving regulatory functions, acting as a transport medium, and providing the environment for most biochemical reactions.

Role of Minerals

Inorganic substances essential for living organisms. They participate in various chemical reactions and help maintain osmotic balance (salinity).

Cell Biology Fundamentals

Organism Types

Unicellular Organisms

Organisms consisting of a single cell that performs all essential life functions.

Multicellular Organisms

Organisms composed of multiple cells, typically organized into tissues and organs, where different cell groups perform specialized functions (division of labor).

Cell Types

Prokaryotic Cell

Characterized by a simple organization; lacks a true, membrane-bound nucleus and most specialized organelles (except ribosomes). Typically possesses a cell wall.

Eukaryotic Cell

Characterized by a complex organization; possesses a distinct, membrane-bound nucleus containing the genetic material and various membrane-bound organelles (e.g., mitochondria, endoplasmic reticulum).

Parts of the Eukaryotic Cell

Cell Membrane

The outer boundary that limits and shapes the cell, regulating the passage of substances.

Cytoplasm

The material within a living cell, excluding the nucleus. It comprises:

  • Hyaloplasm (Cytosol): The jelly-like substance filling the cell.
  • Organelles: Structures suspended in the cytosol, including:
    • Endoplasmic Reticulum (ER)
    • Ribosomes
    • Golgi Apparatus
    • Mitochondria
    • Lysosomes

Nucleus

Contains the cell’s hereditary material (DNA) and controls cell activities. Its main parts are:

  • Nuclear Membrane (Envelope)
  • Nucleoplasm
  • Chromatin

Plant vs. Animal Cell Differences

Animal Cell

  • Lacks a cell wall.
  • Lacks plastids (e.g., chloroplasts).
  • Contains centrioles (within the centrosome).
  • Typically has few, small vacuoles, if any.

Plant Cell

  • Has a rigid cell wall outside the cell membrane.
  • Contains plastids (e.g., chloroplasts for photosynthesis).
  • Most lack centrioles.
  • Typically has a large central vacuole.

Chromosomes

During cell division, the chromatin (DNA and associated proteins) condenses into distinct, rod-shaped structures called chromosomes. Each species has a characteristic number of chromosomes.

Mitosis

A type of cell division resulting in two daughter cells each having the same number and kind of chromosomes as the parent nucleus, typical of ordinary tissue growth.