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4. Control Center: Receives signal from the receptor.

5. Effector: Structure that carries out the response from the control center.

6. Response: What the effector does/

B. For the next 2 scenarios, identify each part of the homeostatic mechanism described.

1. Connie is a long distance runner. Her respiratory rate is based on the amount of CO2 (Carbon Dioxide) in her blood. The normal levels of CO2 are 35-45 mmHg. Chemoreceptors in major blood vessels detect blood CO2 levels and relay that information to the respiratory center in the medulla oblongata (part of the brain stem). The respiratory center controls the activity of the respiratory muscles (diaphragm and intercostals). When Connie exercises, her CO2 levels increase and her respiratory rate increases in an attempt to exhale the excess CO2.

Identify all parts of this homeostatic mechanism (variable, receptor, set point, control center, effector, response.

Variable: Amount of Connie’s exercise

Receptor: Increase in respiratory rate

Set point: 35-45 mmHg

Control center: Brain (medulla oblongata)

Effector: Respiratory muscles

Response: Extra carbon dioxide is exhaled to help Connie maintain her normal respiratory rate

2. Blood calcium (which is normally between 9.0 and 10.5 mg/dl) is controlled by a hormonal control system. Calvin was on a high protein diet that led to a loss of calcium and blood calcium levels of 6.5mg/dl. Calvin’s parathyroid gland detected this lowered level and released parathyroid hormone (PTH). PTH caused an increase in the rate of calcium loss by the bones and reduced the rate of calcium loss by the kidneys.

Identify all parts of this homeostatic mechanism (variable, receptor, set point, control center, effector, response).

Note: this system has 2 effectors and thus 2 responses.

Variable: The calcium rate

Receptor: Parathyroid gland

Set point:...