Characteristics and Classification of Living Organisms Flashcards
What are the seven characteristics of living organisms?
Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, Nutrition (MRS GREN).
Define Movement in living organisms.
An action by an organism or part of an organism causing a change in position or place.
Define Respiration.
The chemical reactions in cells that break down nutrient molecules and release energy for metabolism.
What is Sensitivity?
The ability to detect and respond to changes in the internal or external environment.
Define Growth.
A permanent increase in size and dry mass.
What is Reproduction?
The processes that make more of the same kind of organism.
Define Excretion.
The removal of the waste products of metabolism and substances in excess of requirements.
What is Nutrition?
The taking in of materials for energy, growth, and development.
What is the concept of the classification system?
Organisms are classified into groups by the features they share, showing evolutionary relationships.
What is the sequence of classification?
Kingdom → Phylum → Class → Order → Family → Genus → Species.
Define species.
A group of organisms that can reproduce to produce fertile offspring.
What is the Binomial System?
An internationally agreed system where an organism’s scientific name consists of two parts: genus and species (e.g., Homo sapiens).
How do scientists classify organisms using DNA?
By comparing DNA base sequences; similar DNA indicates closer evolutionary relationships.
What are dichotomous keys used for?
To classify organisms based on visible features through a step-by-step process.
Name the five kingdoms of organisms.
Animals, Plants, Fungi, Prokaryotes, Protoctists.
