The nature and variety of living organisms

• How do plants obtain energy

  Photosynthesis (autotrophic)
• How do animals obtain energy?

  By consuming other organisms (heterotrophic).
• Define respiration


  The release of energy from glucose, either with oxygen (aerobic) or without (anaerobic)
• Products of aerobic respiration?


  Carbon dioxide, water, and ATP.
• What is excretion?


  Removal of waste products from metabolism.
• Main excretory products in animals?


  Carbon dioxide, water, and urea.
• Excretory products in plants


  Oxygen (photosynthesis) and carbon dioxide (respiration).
• Define sensitivity in living organisms.


  Ability to detect and respond to stimuli.
• How do animals respond to their surroundings?

  Through nervous and endocrine systems.
• How do plants respond to their surroundings?

  Using chemical signals (e.g., phototropism and geotropism).
• Define movement in biology.


  Change in position; in animals, it’s called locomotion, plants adjust orientation.
• Define homeostasis.


  Maintaining internal conditions within a suitable range.
• Example of homeostasis in humans?


  Thermoregulation (body temperature control).
• Example of homeostasis in plants?


  Transpiration for temperature regulation.
• What is reproduction?


  Producing more of the same organism type.
• Difference between sexual and asexual reproduction?


  Sexual involves two parents (genetic variety); asexual involves one (clone).
• Define growth


  Increase in number of cells
• Key characteristics of eukaryotic organisms?


  Multicellular or single-celled, with a nucleus.
• Examples of eukaryotic kingdoms?


  Animals, Plants, Fungi, Protoctists.
• Main features of animals?

  Multicellular, no cell wall, no chloroplasts, feed on organic matter, glycogen storage.
• Main features of plants?


  Multicellular, cell wall with cellulose, contain chloroplasts, photosynthetic, starch storage.
• Main features of fungi?


  Often multicellular, chitin cell walls, saprotrophic nutrition, no chloroplasts.
• Main features of protoctists?


  Microscopic, single-celled, some similar to animals, others to plants.
• Difference between eukaryotes and prokaryotes?


  Eukaryotes have a nucleus; prokaryotes (like bacteria) do not.