Biology I

• Biology


  The scietifice study of life.
• Biosphere


  All of the environments on Earth that support life.
• Ecosystem


  An environment that consists of all the organisms living in a particular area, as well as the physical components with which the organisms interact such as air, soil, water and sunlight.
• Community


  The entire array of organisms in an ecosystem.
• Population


  all the individuals of a particular species living in an area.
• Organism


  An individual living thing.
• Organ system


  such as circulatory system or nervous system, consists of several organs that cooperate in a specific function.
• Cell


  The fundamental unity of life.
• Organelle


  a membrane-enclosed structure that performs a specific function in a cell.
• Molecule


  a cluster of small chemical units called atoms held together by chemical bonds.
• Life's heirarchy of organization from largest to smallest.

  Biosphere

  ecosystem

  community

  population

  organism

  organ system

  organ

  tissue

  cell

  organelle

  molecule
• Prokaryotic cells


  A type of cell lacking a membrane-enclosed nucleus and other membrane-enclosed organelles; found only in the domains bacteria and archaea.
• Eukaryotic cells


  A type of cell that has a membrane-enclosed nucleus and other membrane-enclosed organelles. All organisms except bacteria and archaea are composed of this type of cells.
• Genes


  The units of inheritance that transit information from parents to offspring.
• Three Domains of Life

  Bacteria, Archaea, Eurkarya.
• Evolution


  Descent with modification; the idea that living species are descendants of ancestral species that were different from present day ones; also, the genetic changes in a population from generation to generation.
• Natural selection


  A process in which individuals with certain inherited traits are more likely to survive and reproduce than are individuals that do not have those traits.
• Inductive reasoning


  A type of logic in which generalizations are based on a large number of specific observations.
• Hypothesis


  A testable explanation for a set of observations based on the available data and guided by inductive reasoning.
• Deductive reasoning


  A type of logic in which specific results are predicted from a general premise.
• Theory


  A widely accepted explanatory idea that is broader in scope than a hypothesis, generates new hypotheses and is supported by a large body of evidence.
• Controlled experiment


  An experiment in which an experimental group is compared with a control group that varies only in the factor being tested.
• Emergent properties


  New properties that arise with each step upward in the hierarchy of life, owing to the arrangements and interactions of parts as complexity increases.
• 7 characteristics of life

  Movement: all living things move (internal or external)

  Respiration: all living things use oxygen

  Sensitivity: all living things can respond to changes in their surroundings

  Growth: all living things develop

  Reproduction: all living things make more of their own type

  Excretion: all living things get rid of waste – like when humans go to the toilet

  Nutrition: animals will eat food for energy and nutrients
• Symbiosis: A relationship between two different organisms that live in close association with each other.
• Mutualism: A relationship in which both organisms benefit from the interaction.
• Commensalism: one organism benefits and the other does not but is not harmed.
• Parasitism: A relationship between two organisms in which one organism benefits at the expense of the other.
• The system of biological kingdoms is the way in which science classifies living things according to their ancestry over the course of evolution.
• The kingdom Animalia is the most evolved and is divided into two large groups - vertebrates and invertebrates. These are multi-celled, heterotrophic eukaryotes with aerobic respiration, sexual reproduction and the ability to move.
• Trees, plants and other species of vegetation make up part of the Plantae kingdom - one of the oldest, and characterised by its immobile, multicellular and eukaryotic nature.
• The fungi kingdom: These multicellular aerobic heterotrophic eukaryotes have chitin in their cell walls, feed off other living things, and reproduce through spores.
• This group is the most primitive of the eukaryotics and all the others are descendants of it. The Protista kingdom is paraphyletic - it contains the common ancestor but not all its descendants - and it includes those eukaryotic organisms that are not deemed to be animals, plants or fungi such as protozoa.
• Monera Kingdom: This is the kingdom of microscopic living things and groups together the prokaryotes (archaea and bacteria). This group is present in all habitats and is made up of single-cell things with no defined nucleus. Most bacteria are aerobic and heterotrophic, while the archaea are usually anaerobic and their metabolism is chemosynthetic.
• Producers, also known as autotrophs, make their own food. They make up the first level of every food chai
• The second trophic level consists of organisms that eat the producers. These are called primary consumers, or herbivores. Deer, turtles, and many types of birds are herbivores.
• Higher-level consumers (i.e., secondary, tertiary, and above) can be carnivores (animals that eat other animals) or omnivores (animals that eat both plants and animals). Omnivores, like people, consume many types of foods.
• Detritivores are organisms that eat nonliving plant and animal remains.
• Decomposers complete the cycle of life, returning nutrients to the soil or oceans for use by autotrophs.
• Mesocarnivores are animals that depend on meat for at least 50 percent of their diet.