Ch. 1 - Characteristics and classification of living organisms Flashcards
What is biology?
The study of organisms
What is an organism?
A living thing
What do all organisms share?
Seven key characteristics
What are the seven characteristics of living organisms?
- Movement
- Excretion
- Sensitivity
- Growth
- Reproduction
- Nutrition
- Respiration
What is movement?
The ability of an organism to change position or place
Do plants perform movement?
Yes. Furthermore, their chloroplasts are moving about inside them
What is respiration?
Respiration is the chemical reactions in cells that break down nutrient molecules (usually from glucose) and release energy for metabolism
What is sensitivity?
The ability to detect and respond to changes in the environment (either internal environment or external)
What is growth?
Permanent increase in size and dry mass (pufferfish - no)
How to measure growth with dry mass?
- Comparing masses of identical organisms over time
- Kill one
- Let it dry
- Find mass without water
- Repeat with other organisms in the future and compare
What is reproduction?
The processes with make more of the same kind of organisms
What is excretion?
Process by which an organism gets rid of unwanted substances (either toxic or in excess)
What is nutrition?
Taking in materials which contain chemicals and energy for growth, development, and energy
How do biologist classify living organisms?
Based on how closely they think they are related
What is a common ancestor?
A species that lived in the past and is thought to have given rise to several different species
How else are living organisms classified?
Based on shared characteristics which suggest they are related
What is a species?
Smallest group in which we can fit living organisms, their offsprings are fertile
Example of infertile offspring?
Mule (from horse + donkey)
How do we name living organisms?
Through the binomial system
What is the binomial system?
An international agreed way of scientifically naming species (first name: genus, second name: species)
What is a genus?
Group of species that share similar features and a common ancestor
How to identify organisms?
Through dichotomous key
What is a dichotomous key?
A set of descriptions given two at a time from which you have to choose only one
What are kingdoms?
Biggest group in which we can divide living organisms
Characteristics of the animal kingdom?
- Have nucleus
- Don’t have cell walls or chloroplasts
- Feed on organic substances made by other living organisms
- Move freely