7&8 LESSON_Q3

• Biodiversity


  The variety of life forms in a particular ecosystem
• The Philippines is known for its very rich biodiversity
• The Philippines has more than 52,177 described species of which more than half is found nowhere else in the world
• The Philippines is considered a biodiversity hotspot because it is continuously experiencing an alarming rate of environmental destruction like damage of coral reefs, forests, and other similar important resources
• Ecosystem


  A community of organisms that live, feed, and interact with the environment
• Exponential growth


  Population growth in which there is a constant increase in the number of organisms
• Logistic growth


  Population growth in which the growth rate decreases with increasing number of organisms, until it becomes zero when the population reaches its carrying capacity
• Population density


  Measurement of population per unit area
• Carrying capacity


  The maximum number of individuals that an environment can support
• The human population is growing at an exponential rate
• The Philippine eagle (Pithecophaga jefferyi) is considered an endangered species
• Endangered species means the death rate of Philippine eagles is greater than the birth rate
• The maximum number of individuals that an environment can support is termed carrying capacity
• Based on the graph, the carrying capacity of the rabbit population is 65
• Based on the graph, there is a rapid growth in the rabbit population between mid-May to mid-June
• Evolution


  The gradual change in the characteristics of a population of organisms over successive generations
• Fitness


  The ability of an organism to survive and reproduce in a particular environment
• Adaptation


  A characteristic that helps an organism survive and reproduce in its environment
• Survival of the Fittest

  The process by which organisms best adapted to their environment tend to survive and produce more offspring
• Natural Selection


  The process by which certain traits become either more or less common in a population based on their relative fitness
• Homologous Structures


  Structures in different organisms that have the same basic form and function, though they may have different appearances
• Direct economic value


  The species is said to have direct economic value if their products are sources of food, medicine, clothing, shelter, and energy
• Direct economic value


  • Vinblastine and vincristine extracted from the rosy periwinkle used in chemotherapy
  • Lagundi extracted for cough syrup production
• Indirect economic value


  The species has indirect economic value if there are benefits produced by the organism without using them
• Indirect economic value


  • Cattail plant stabilizing wet banks of rivers and lakes
  • Cattails ability to treat wastewater
• Aesthetic value


  Species that provide visual or artistic enjoyment, like a forested landscape and the calming beauty of a natural park
• Biodiversity is very important because it sustains the flow of energy, the food web on earth and contributes to environmental stability
• Stability of an ecosystem


  The resilience to withstand changes that may occur in the environment
• Population


  A group of organisms of the same species that live in a certain area
• Birth rate (natality)


  The number of births in a population
• Death rate (mortality)


  The number of organisms that are dying in a population
• Density-independent limiting factors


  Factors that regulate a population's growth and are not influenced by population density
• Density-independent limiting factors


  • Natural disasters, temperature, sunlight, human activities
• Density-dependent limiting factors


  Factors that regulate a population's growth and are influenced by population density
• Carrying capacity


  The maximum number of organisms that can be supported by the available resources in a particular environment
• Exponential population growth


  Rapid growth of a population before it reaches its carrying capacity
• Carrying capacity


  The maximum number of organisms that an environment can support
• Population growth


  1. Rapid growth before reaching carrying capacity

  2. Leveling off when carrying capacity is reached
• When a population reaches a certain size

  There won't be enough resources (food, shelter, water) for all organisms
• Population reaching maximum number of organisms that can be supported

  Population stops growing