Homeostasis Practice

Master homeostasis! Practice feedback loops, identify components, and interpret graphs.

Match the components of feedback loops with their definitions Stimulus An event that causes change in the body's internal conditions Effector Structure that carries out a response Receptor Structure that detects the change in the body's internal environment Control center Structure that determines the appropriate response Scenario 1As a person gets dehydrated, their blood becomes thicker and harder to pump. As this happens, the kidneys stop producing urine and the water from urine is redirected for use in the blood.What is the stimulus in scenario 1? Low water concentration in the blood High water concentration in the blood High sugar concentration in the blood Low sugar concentration in the blood What type of feedback loop is described in scenario 1? Positive feedback, stimulus is reversed Negative feedback, stimulus is intensified Positive feedback, stimulus is intensified Negative feedback, stimulus is reversed Scenario 2As a person’s blood sugar lowers, the pancreas releases a chemical called glucagon to return the blood sugar back to normal.What is the stimulus in scenario 2? High blood sugar High body temperature Low blood sugar Low body temperature What type of feedback loop is described in scenario 2? Positive feedback, stimulus is amplified Negative feedback, stimulus is opposed Positive feedback, stimulus is opposed Negative feedback, stimulus is amplified Scenario 3Rapid growth during puberty causes the release of more growth hormones.What is the stimulus in scenario 3? High blood pressure Slow growth Low blood pressure Rapid growth What type of feedback loop is described in scenario 3? Positive feedback, stimulus is enhanced Negative feedback, stimulus is negated Positive feedback, stimulus is negated Negative feedback, stimulus is enhanced Senario 4As a person’s blood sugar rises, the beta cells in the pancreas releases a hormone called insulin to return the blood sugar back to normal.What is the stimulus in scenario 4? High blood pressure High blood sugar Low body temperature Low water concentration in the blood What type of feedback loop is described in scenario 4? Positive feedback counteracts the activity of the stimulus. Negative feedback counteracts the activity of the stimulus. Negative feedback enhances the activity of the stimulus. Positive feedback enhances the activity of the stimulus. Scenario 5When a blood vessel is injured, chemicals are released to activate platelets (small disk-shaped cell fragments) to stop bleeding. Platelets then release more chemicals to activate even more platelets to help stop bleeding.What is the stimulus in scenario 5? High blood pressure High blood sugar Childbirth Bleeding What type of feedback loop is described in scenario 5? Negative feedback disrupts homeostasis by activating a response to counteract the change. Negative feedback produces a response that intensifies the stimulus in the same direction. Positive feedback produces a response that intensifies the stimulus in the same direction. Positive feedback produces a response that reverses the change to maintain homeostasis. Scenario 6If calcium in the blood decreases, the parathyroid gland senses the decrease and secretes a hormone that releases calcium from the bones into the bloodstream, restoring the calcium blood levels.What is the stimulus in scenario 6? High blood sugar Low calcium levels Bleeding Low milk production What type of feedback loop is described in scenario 6? Negative feedback because it opposes positive feedback responses Negative feedback because it returns the body to its set point Positive feedback because it helps the body Negative feedback because it is harmful for the body Scenario 7Examine the diagram of blood oxygen levels regulation in our body then answer the questions that follow.What is the control center in scenario 7? Blood Bone Kidney Red blood cells What is the effector in scenario 7? Blood Bone Kidney Decreased red blood cell count What type of feedback loop is described in scenario 7? Positive feedback returns the system to its set point Negative feedback returns the system to its set point Positive feedback moves the system further from its set point Negative feedback maintains a system at its set point Scenario 8Examine the diagram of childbirth then answer the questions that follow.What is the receptor in scenario 8? Brain Pituitary gland Uterus Nerves in the cervix What is the effector in scenario 8? Brain and pituitary gland Uterus Blood Nerves in the cervix What type of feedback loop is described in scenario 8? Negative feedback, the activity of the stimulus is counteracted Negative feedback, the activity of the stimulus is enhanced Positive feedback, the activity of the stimulus is enhanced Positive feedback, the activity of the stimulus is maintained Use the graph below to answer the question that follows.Which of the following statements are true about this graph? This graph is an example of positive feedback because the blood pressure varies around the set point. This graph is an example of negative feedback because the blood pressure varies around the set point. This graph is an example of positive feedback because the blood pressure continues to rise. This is graph is an example of negative feedback because the blood pressure continues to decrease. Use the graph below to answer the questions that follow.What is the set point for blood sugar? 80 mg 90 mg 100 mg 145 mg A disruption in homeostasis is indicated by a blood sugar level change between points _. B and A C and E H and G D and F The action of a feedback mechanism is indicated by a blood sugar level change between points _. B and A C and E A and C E and F According to the graph, maintaining blood sugar levels is an example of which type of feedback? Positive feedback Negative feedback There isn't enough information to determine Use the graph below to answer the question that follows.Which of the following statements are true about the graph. This is an example of positive feedback because the platelet count gets back to the set point. This is an example of negative feedback because the platelet count varies around the set point. This is an example of positive feedback because the platelet count continues to grow. This is an example of negative feedback because the platelet count continues to grow.