SBI4U: Biology, Grade 12, University Preparation. Unit 4: Homeostasis Test ... 3.
The hypothalamus controls the anterior pituitary with which of the following?
SBI4U: Biology, Grade 12, University Preparation Unit 4: Homeostasis Test Teacher’s Notes/ Answer Key The following test will be assessed according to the following 4 categories. Knowledge & Understanding (K&U) Thinking & Investigation (T&I) Communication (C) Application (A)
27 marks 13 marks 10 marks 10 marks
Total number of marks = 60
Multiple Choice (K & U /15 marks) 1. The autonomic nervous system: a) controls voluntary muscles b) is involved in conscious thought c) is the centre for learning d) controls unconscious life-sustaining activities e) none of the above 2. Which of the following statements about hormones is incorrect? a) they are produced by glands b) they travel to different areas of the body c) they are carried by the blood d) they are used to communicate between different individuals e) they cause responses in target cells 3. The hypothalamus controls the anterior pituitary with which of the following? a) releasing factors b) thalamus messenger c) third messengers d) antibodies e) acetylcholine 4. Acetylcholine works: a) by effecting in the nucleus of a cell and starting transcription b) in neuromuscular junction c) initiates the formation of steroids d) is important in the action potential
5. The posterior pituitary secretes: a) oxytocin and antidiuretic hormone b) thyroid-stimulating and adrenocorticotropic hormone c) insulin and glucagons d) growth hormone and prolactin 6. An example of a functional similarity between the nervous system and the endocrine system is: a) both systems secrete hormones into the bloodstream b) compounds used as hormones by the endocrine system may also function as neurotransmitters inside the CNS c) they use the same cells d) both produce very specific responses to environmental stimuli 7. Neurons communicate with one another and with effectors by: a) releasing chemical neurotransmitters b) receptor binding at the cell membrane c) interacting with a hormone and a receptor complex d) releasing chemicals into the bloodstream 8. The release of hormones by endocrine cells alters the: a) the rate at which chemical neurotransmitters are released b) metabolic activities of many tissues and organs simultaneously c) the nervous system d) function of muscles 9. The most notable effect of ADH produced in the posterior pituitary is to: a) increase the amount of water lost at the kidneys b) increase or decrease calcium ion as a second messenger c) decrease the amount of water lost at the kidneys d) lowers blood pressure 10. Peptide hormones affect target organ cells by: a) binding to receptors in the cytoplasm b) causing second messengers to be released when receptor binding occurs at the membrane surface c) binding to target receptors in the nucleus d) causing steroid production in the cell
11. Release of controlling hormones by the anterior pituitary is regulated by: a) neural control from the hypothalamus b) a negative feedback system c) none of these d) both of these 12. Some nerves of the autonomic nervous system terminate at the pacemaker cells of the heart. These neurons secrete acetylcholine which decreases the heart rate. This is an example of: a) endocrine control b) exocrine control c) neural control d) hormonal control 13. For the action potential to be reached, a) the membrane must be out of the relative refractory period. b) the Na+ entering the cell must exceed the K+ leaving the cell c) the stimulus must reach or exceed the threshold. d) all of the above 14. The ‘master gland’ of the endocrine system: a) is the pineal gland b) the pituitary gland c) the hypothalamus d) the pancreas 15. Epinephrine and norepinephrine are not only hormones, but they are also: a) neurotransmitters in the central nervous system b) neurotransmitters in the sympathetic nervous system c) enzymes d) all of the above 16. Which of the following is not true for cortisol? a) cortisol is a glucocorticoid hormone b) cortisol tends to elevate blood glucose levels c) cortisol is made in the adrenal cortex d) cortisol stimulates the fight – flight response.
Short Answer (T & I /13, C /10) 1. Describe how the nervous system and the endocrine system work together in the fight-flight response. (T & I / 5) -
response using the sympathetic and parasympathetic nervous – one to stimulate the response and the other to bring it back to equilibrium uses direction from hypothalamus, pituaritary, and adrenal gland to secrete stress hormones – adrenaline – increase alertness, increase heart rate, breathing, redirect blood to muscles, and heart
2. Explain what negative feedback is and how it works using insulin/glucagon(T & I / 5) insulin – promotes glucose uptake in blood - lowers blood sugar – promotes glucagons release - stimulates glycogen formation Glucagon – stimulates glycogen breakdown - raises blood sugar – promotes insulin release
3. A new toxin is discovered (hypothetically) that has entered into the environment. Scientists are very concerned because it blocks Na+ channels. Explain why they should take this seriously and what this would mean to an organism? (T & I /3) - Na+ channels will not allow Na+ back into the axon, so nerve will not re-establish a potential and will not fire – not more brain activity
4. During a physical examination, a doctor will usually hit a patient's knee on one side with a small hammer. Instantly the leg jerks upward. Through the aid of a diagram, Explain what the doctor is testing and indicate the components involved in this process. ( C /5) -The involuntary knee jerk reflex is being tested, reflex arc. The sensory receptor relays to a sensory neuron, which carries a signal to the spinal column. An interneuron passes impulses to a motor neuron from the sensory neuron. The knee jerks up when muscle receives signal and the brain receives message an instant later
5. Construct a feedback model that illustrates how the body reacts when the internal temperature decreases. (C /5) - The set point for human body temperature is 37°C. - Thermoreceptors in the skin sense temperature. - The brain receives information. - Effectors for regulating body temperature include the following: ◦ blood vessels in the skin that constrict to direct blood away from the skin, thus warming the body, ◦ shivering, a rapid contraction of muscles that warms the body ◦ behaviour such as putting on a hoodie to warm the body
Diagrams (K & U/17) 1. Label the following diagram. (K&U /6) Identify the regions or molecules 2. _Synaptic vesicle___ 4. _Synapse____ 5. __Neurotransmitter Receptor___ 7. _Neurotransmitter__ A. __Presynaptic membrane/cell__ B. Postsynaptic membrane/cell
2. Label the following diagram (K&U /5) 1. _Schwann cell____ 2. _Myelin Sheath____ 3. __Axon Terminal____ 4. __Node of Ranvier____ 5. __Cell body___
Long Answer (A /10) 1. Many professional athletes choose to use performance enhancing drugs to provide them with an advantage during competition. a. Choose a performance enhancing drug and indicate 3 advantages it provides to an athlete. (4 Marks) -Answers will vary from student to student -any drug that is performance enhancing is fine, but must be able to provide its advantages for full marks
b. Indicate 1 short term and 1 long term effect as a result of taking these chemicals and explain what changes are occurring in the body. (6 Marks) -Answers will vary from student to student - must give an example and provide explanation of what is occurring to get full marks
