Characteristics of Life Quiz

Study Notes

Characteristics of Life

Living organisms display unique characteristics distinguishing them from non-living entities.
These characteristics include organization, metabolism, growth, adaptation, response to stimuli, reproduction, and homeostasis.
Organization: Living structures range from atoms to molecules, cells, tissues, organs, organ systems, and organisms.
Metabolism: Chemical reactions (anabolism and catabolism) support life functions, including energy acquisition and use.
Growth: Organisms increase in size and complexity through cell division and material accumulation.
Adaptation: Species evolve, adjusting to changing environments through natural selection. Favourable traits enhance survival and reproduction.
Response to Stimuli: Organisms react to environmental changes, from plant phototropism to animal behaviours.
Reproduction: Creation of similar organisms ensures species continuity, achieved through sexual or asexual methods.
Homeostasis: Maintaining a stable internal environment (e.g., temperature, water balance) is crucial for survival.

Biological Organization

Biological entities exhibit hierarchical order.
Atoms combine into molecules, which form macromolecules, leading to organelles.
These organelles work within the cell.
Cell groups form tissues, tissues form organs, organs form organ systems, and these systems contribute to the organism.

Biodiversity

Biodiversity encompasses the variety of life on Earth, encompassing genes, species, and ecosystems.
Genetic diversity refers to the variations in genes within a species.
Species diversity reflects the variety of species in an area.
Ecosystem diversity includes the diverse habitats, communities, and ecological processes in a region.

Classification of Organisms

Organisms are grouped based on shared traits, reflecting evolutionary links.
The modern system classifies using evolutionary relationships.
The hierarchical system (Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species) organizes organisms based on shared history.

Cell Theory

All life forms consist of cells or cell derivatives.
The cell is the fundamental unit of structure and function in living organisms.
All cells originate from pre-existing cells.

Types of Cells

Prokaryotic cells: Lack a nucleus and membrane-bound organelles (e.g., bacteria, archaea).
Eukaryotic cells: Contain a nucleus and membrane-bound organelles (e.g., animals, plants, fungi, protists).

Energy Flow in Ecosystems

Organisms derive energy for survival from their environment.
Food chains and webs depict energy flow within ecosystems.
Producers (autotrophs) generate their own food through photosynthesis or chemosynthesis.
Consumers (heterotrophs) obtain energy by consuming other organisms.
Decomposers break down dead organisms, returning nutrients to the ecosystem.

Evolution

Evolution is the inherited change in populations over generations, supported by fossil, anatomy, and genetic evidence.
Natural selection is a driving force of evolution. Organisms with advantageous traits are more likely to survive and reproduce.

Ecology

Ecology studies the interactions between organisms and their environment at various levels (populations, communities, ecosystems).
Key concepts include population dynamics, community interactions, ecosystem processes, and biomes.
Biomes are large-scale ecological communities defined by climate and the organisms adapted to it.

Description

Test your knowledge of the essential characteristics that define living organisms. This quiz covers topics such as organization, metabolism, growth, adaptation, response to stimuli, reproduction, and homeostasis. Understand how these traits distinguish life from non-living matter.