Characteristics and classification of living organisms

• What is biology the study of?

  Organisms
• What defines an organism?


  A complete living thing, such as a human, animal, or plant
• How many characteristics do all organisms share?

  Seven characteristics
• What is growth in organisms?


  The process of becoming larger by the growth of cells and adding new cells
• What is the definition of movement in organisms?

  An action causing a change of position or place
• How do animals and plants differ in movement?

  Most animals can move their whole body, while plants can slowly move parts of themselves
• What does sensitivity in organisms refer to?

  The ability to pick up information about changes in the environment and react to them
• What is excretion in organisms?


  The removal of unwanted or toxic waste products from the body
• What is reproduction in organisms?


  The ability to make new organisms of the same species
• What is nutrition in organisms?

  The process of taking substances from the environment to provide energy or materials for new cells
• What is respiration in organisms?

  The breakdown of glucose and other substances to release energy
• What is metabolism?


  All chemical reactions that take place in living organisms, including respiration
• How do plants demonstrate movement?

  By slowly moving parts of themselves and having chloroplasts that move within their cells
• How can growth be measured in organisms?

  By finding the dry mass of organisms over a period of time
• What is the definition of a species?

  A group of organisms that can reproduce with each other to produce fertile offspring
• What is the significance of the binomial naming system?


  It provides a standardized way to name species using two words
• What does the first name in the binomial system represent?

  The genus of the organism
• How is the second name in the binomial system written?

  With a lowercase letter
• What is a dichotomous key?


  A tool that helps identify organisms by providing pairs of descriptions
• What does 'dichotomous' mean?

  Branching into two
• What are the seven characteristics of living organisms?

  1. Growth
  2. Movement
  3. Sensitivity
  4. Excretion
  5. Reproduction
  6. Nutrition
  7. Respiration
• What are the key terms related to the characteristics of organisms?

  • Organism: a living thing
  • Respiration: chemical reactions that release energy
  • Metabolism: all chemical reactions in living organisms
  • Sensitivity: ability to detect and respond to changes
  • Growth: permanent increase in size and dry mass
  • Reproduction: processes that make more of the same kind of organism
  • Excretion: removal of waste products
  • Nutrition: taking in materials for energy, growth, and development
• What is the classification system used by biologists?

  • Classification: putting organisms into groups based on shared features
  • Common ancestor: a species that gave rise to several different species
  • Species: a group of organisms that can reproduce to produce fertile offspring
  • Binomial system: a two-part naming system for species
• What is the significance of a common ancestor in classification?

  • Indicates relatedness among species
  • Helps understand evolutionary history
  • Provides insight into shared characteristics
• What are the features of the binomial naming system?

  • Two-word names
  • First word: genus (capitalized)
  • Second word: species (lowercase)
  • Italicized or underlined when written
• How does a dichotomous key function?

  • Provides pairs of descriptions
  • Guides user to identify an organism
  • Each choice leads to another pair of descriptions
• What is the purpose of using a key in biology?

  To identify organisms based on their characteristics
• What is the first step when using a key to identify an organism?

  Choose one of the animals you are going to identify
• If organism B has jointed limbs, which step do you go to next in the key?

  Step 2
• How do the statements in a key typically relate to each other?

  They are opposites of one another
• What should you remember when writing your own keys?

  • Each pair of statements should be opposites
  • Do not mix different ideas into a pair of statements
• What is the smallest group into which living organisms are classified?

  The species
• What are the two most familiar kingdoms of living organisms?

  • Animal kingdom
  • Plant kingdom
• What is a characteristic feature of animals?

  Most animals can move actively
• What do animal cells lack that plant cells have?

  Cell walls and chloroplasts
• How do animals obtain their food?

  By feeding on organic substances made by other living organisms
• What is a common feature of flowering plants?

  They have flowers, roots, and stems
• What pigment is responsible for the green color in plants?

  Chlorophyll
• What process do plants use to make food using sunlight?

  Photosynthesis
• What do plant cells have that animal cells do not?

  Cell walls made of cellulose