Introduction to Biology

Study Notes

Introduction to Biology

Biology is the scientific study of life and living organisms.
It encompasses various disciplines, including botany, zoology, microbiology, and genetics.
Key aspects include cells, genetics, evolution, ecology, and the structure and function of organisms.
Life is characterized by several defining features, including:
- Organization: Living organisms are arranged in complex structures.
- Metabolism: The chemical processes within organisms to maintain life.
- Growth and development: Organisms grow and change over their lifetime.
- Reproduction: Organisms produce offspring, passing on genetic material.
- Response to stimuli: Living things react to changes in their environment.
- Homeostasis:Maintaining internal balance.
- Adaptation: Organisms adapt to their environment over generations.

Levels of Biological Organization

Biological organization encompasses various hierarchical levels, from the smallest to the largest.
Atoms combine to form molecules.
Molecules form macromolecules, which contribute to cell structure and functions.
Cells are the basic units of life, forming tissues.
Tissues combine to form organs.
Organs collaborate in organ systems.
Organ systems form a multicellular organism (e.g., animal or plant).
Organisms interact in populations, communities, and ecosystems.
Finally, the biosphere consists of all interconnected ecosystems on Earth.

Basic Chemistry for Biology

Carbon is a key element in living matter, forming the backbone of many biological molecules.
Water is essential for life; its properties include polarity, high specific heat, and ability to act as a solvent.
Four major classes of biological macromolecules: carbohydrates, lipids, proteins, and nucleic acids.
- Carbohydrates: Primary energy source; structural components.
- Lipids: Store energy, insulation; component of cell membranes.
- Proteins: Diverse functions — structural, enzymatic, transport, etc.
- Nucleic acids (DNA and RNA): Carry genetic information.

Cell Structure and Function

Cells are the fundamental units of life; they are diverse in structure and function.
There are two main types of cells: prokaryotic and eukaryotic.
Prokaryotic cells are smaller and simpler, lacking membrane-bound organelles.
Eukaryotic cells are larger and more complex, possessing membrane-bound organelles (e.g., nucleus, mitochondria).
Key organelles:
- Nucleus: Stores genetic material (DNA).
- Mitochondria: Powerhouse of the cell, performing cellular respiration.
- Ribosomes: Synthesize proteins.
- Endoplasmic reticulum (ER): Involved in protein synthesis and lipid metabolism.
- Golgi apparatus: Processes and packages proteins.
- Vacuoles: Storage compartments

Cellular Processes

Cellular respiration: The process by which cells break down glucose to release energy.
Photosynthesis: The process by which plants and some other organisms convert light energy into chemical energy.
Cell division: Mitosis and meiosis are critical for growth, repair, and reproduction.
- Mitosis: Cell division for growth and repair.
Meiosis: Cell division for sexual reproduction.

Genetics

Hereditary information is passed through DNA.
DNA is organized into genes, which code for specific proteins.
Genes can be expressed (turned on) or repressed (turned off).
Mutation is a change in the DNA sequence.
Chromosomes are structures that organize DNA in cells.

Biological Diversity

The vast array of life on Earth encompasses numerous species.
Biological diversity (biodiversity) is the variety of life at all levels of biological organization.
Evolutionary processes have led to the diversity of species seen today.
Darwin's theory of evolution by natural selection: Species change over time due to inheritable variations that affect survival/reproduction.
Adaptation: Organisms adapt to their environment over generations.

Description

This quiz covers the fundamentals of biology, including the study of living organisms and the key characteristics that define life. You'll explore various disciplines such as botany, zoology, and genetics, as well as the levels of biological organization. Test your knowledge on crucial concepts like metabolism, reproduction, and adaptation.