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- THE BIG PICTURE OF BIOLOGY
- BIG IDEA 1: EVOLUTION
- 1A: Evolution - Change in Genetic Makeup
- 1B: Evolution by Common Descent
- 1C: Life Continues to Evolve
- 1D: Theories of the History of Life
- BIG IDEA 2: ORGANISMS USE ENERGY AND MOLECULES TO GROW, REPRODUCE, AND MAINTAIN HOMEOSTASIS
- 2A: PHOTOSYNTHESIS, CELLULAR RESPIRATION, AND ENERGY
- 2B: CELL HOMEOSTASIS - CELL MEMBRANE PROCESSES
- 2.C: HOMEOSTASIS - POSITIVE AND NEGATIVE FEEDBACK
- 2.D: Growth and dynamic homeostasis of a biological system are influenced by changes in the system’s environment.
- 2.E: Many biological processes involved in growth, reproduction and dynamic homeostasis include temporal regulation and coordination.
- BIG IDEA 3: LIVING SYSTEMS STORE, RETRIEVE, TRANSMIT, AND RESPOND TO INFORMATION
- 3.A: DNA TRANSCRIPTION AND TRANSLATION
- 3.B: GENE REGULATION - TRANSCRIPTION AND TRANSLATION
- 3C: GENETIC MUTATIONS AND VIRUSES
- 3D: CELL COMMUNICATION AND SIGNAL TRANSDUCTION
- 3E: ANIMAL BEHAVIOR AND NERVOUS SYSTEM
- BIG IDEA 4: BIOLOGICAL SYSTEMS INTERACT IN COMPLEX WAYS
- 4A: BIOCHEMISTRY AND CELL BIOLOGY
- 4.B: Competition and cooperation are important aspects of biological systems.
- 4.C: Naturally occurring diversity among and between components within biological systems affects interactions with the environment.
- RESULTS AND RESOURCES
- AP BIO LABS: BIG IDEA 1 - EVOLUTION
- AP BIO LABS: BIG IDEA 2 -
- AP BIO LABS: BIG IDEA 3
- AP BIO LABS: BIG IDEA 4
Enduring understanding 2.C: Organisms use feedback mechanisms to regulate growth and reproduction, and to maintain dynamic homeostasis.
Essential knowledge 2.C.1: Organisms use feedback mechanisms to maintain their internal environments and respond to external environmental changes.
Negative feedback mechanisms maintain dynamic homeostasis for a particular condition (variable) by regulating physiological processes, returning the changing condition back to its target set point.
To foster student understanding of this concept, instructors can choose an illustrative example such as:
Positive feedback mechanisms amplify responses and processes in biological organisms. The variable initiating the response is moved farther away from the initial set-point. Amplification occurs when the stimulus is further activated which, in turn, initiates an additional response that produces system change.
Students should be able to demonstrate understanding of the above concept by using an illustrative example such as:
• Lactation in mammals
• Onset of labor in childbirth
• Ripening of fruit
Alteration in the mechanisms of feedback often results in deleterious consequences.
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Diabetes mellitus in response to decreased insulin
• Dehydration in response to decreased antidiuretic hormone (ADH)
• Graves’ disease (hyperthyroidism)
• Blood clotting
To foster student understanding of this concept, instructors can choose an illustrative example such as:
- Operons in gene regulation
- Temperature regulation in animals
- Plant responses to water limitations
Positive feedback mechanisms amplify responses and processes in biological organisms. The variable initiating the response is moved farther away from the initial set-point. Amplification occurs when the stimulus is further activated which, in turn, initiates an additional response that produces system change.
Students should be able to demonstrate understanding of the above concept by using an illustrative example such as:
• Lactation in mammals
• Onset of labor in childbirth
• Ripening of fruit
Alteration in the mechanisms of feedback often results in deleterious consequences.
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Diabetes mellitus in response to decreased insulin
• Dehydration in response to decreased antidiuretic hormone (ADH)
• Graves’ disease (hyperthyroidism)
• Blood clotting
Essential knowledge 2.C.2: Organisms respond to changes in their external environments.
a. Organisms respond to changes in their environment through behavioral and physiological mechanisms.
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Photoperiodism and phototropism in plants
• Hibernation and migration in animals
• Taxis and kinesis in animals
• Chemotaxis in bacteria, sexual reproduction in fungi
• Nocturnal and diurnal activity: circadian rhythms
• Shivering and sweating in humans
To foster student understanding of this concept, instructors can choose an illustrative example such as:
• Photoperiodism and phototropism in plants
• Hibernation and migration in animals
• Taxis and kinesis in animals
• Chemotaxis in bacteria, sexual reproduction in fungi
• Nocturnal and diurnal activity: circadian rhythms
• Shivering and sweating in humans
