Bio1152 Chapter 39 Plant Responses to Internal and External Signals
  1. Plants can respond to stimuli in the environment in a process called          .

  2. Pigments such as              can sense light and regulate         responses.

  3. The response involves signal               of the stimulus, often involving a         messenger to          the signal.

  4. Several           play important roles in regulating tropic responses.
    •         are released by the         meristem and at low concentrations stimulate cell             in young developing shoots.

    •             interact with auxin to stimulate cell division and                  , and also control         dominance.

    •               promote       elongation,        growth, and       germination.

    •           is produced in response to           . A change in the balance of        and ethylene controls leaf abscission.

  5.              (geotropic) responses to gravity may be mediated by the settling of             . Roots show           gravitropism, while stems show           gravitropism.

  6.               responses to             stimuli enable        to coil their tendrils around supports. Touch can also affect plant morphology by                      .

  7. Plant defenses against            include thorns and spines. Some plants even "recruit"          for defense.

Bio1152 Chapter 40 Basic Principles of Animal Form and Function
  1. Animals, like other organisms, have        that closely serve            .

  2. Evolutionary              reflects different species' independent             to a similar environmental challenge.

  3. Animals must maintain adequate          -to-volume ratio to exchange materials with the environment, and often have highly         internal surfaces specialized for exchanging materials.

  4. Animal tissues are classified into four main categories.
    • Epithelial tissue cover the outside of the body and lines organs within the body.

    • Connective tissue bind and support other tissues.

    • Muscle tissue is composed of long cells called muscle         capable of contracting in response to        signals.

    • Nervous tissue sense stimuli and transmits signals throughout the animal.

  5. Cellular              produces the energy-containing molecules      (Adenosine TriPhosphate), which powers cellular work.

  6. Animals maintain an internal temperature in a process called                   , which may consume a significant portion of its energy         .

  7. In humans,                   is controlled by a region of the brain called the hypothalamus.

  8. Organisms exchange heat with the environment by four processes:            ,              ,             , and             .

    • The                system provides insulation to reduce heat exchange with the environment.

    • Many marine mammals and birds have                 heat exchangers to reduce heat loss.

    • Animals can also thermoregulate by behaviors such as              cooling, body           , and            .

  9. Some animals undergo a seasonal              triggered by a long-term decrease in metabolism.