Unformatted text preview: Name: Life Sciences 2
Midterm #1 Question # Points #1
Total 1 Name: Two and Three Point Questions 1) Identify two of the three tissue subdivisions that form from somites and an adult structure that develops from each. (2 points) 2) During the blastocyst stage of vertebrate development, the inner cell mass, or embryoblast, is composed of two layers. What are the names of the two layers and what does each layer become? (2 points) 3) Why is each vertebrae formed from two different pairs of somites and each muscle from a single somite? (2 points) 2 Name: 4) Hormones of the vertebrate endocrine system fit into two major categories. What are these categories and how do they differ in their (1) molecular structure, and (2) their evolvability? (2 points) 5) Diagram the HPA axis, identify the principal hormones and their effects. (3 points) 6) List two differences between the endocrine system and the immune system in terms of their communications. (2 points) 3 Name: 7) A neuron that sends a signal to your stomach to decrease secretion of digestive enzymes during a stressful experience can be classified as (circle one of each group): (2 points) Afferent / Efferent Somatic / Sympathetic / Parasympathetic Cranial / Spinal 8) Why does muscle fiber length affect the force that a muscle can produce during a contraction? (2 points) 9) Identify the two components of the autonomic nervous system. Where do the nerves for each component exit the CNS? List a functional role for each component. (3 points) 4 Name: Four, Five and Six Point Questions 10) A) Name three “tubes” that arise during embryonic development and describe the process that gives rise to each tube. Be brief and concise. (3 points) Which tube is formed of both endoderm and mesoderm, and what is its functional significance? (2 points) B) 11)Identify the metabolic crisis at the end of pregnancy and explain how this crisis stimulates parturition. (5 points) 5 Name: 12) On the graph below complete the following objectives and answer the associated questions: A) Draw an action potential. (0.5 points) B) Label and provide the units for the X and Y axes. (0.5 points) C) Label the resting membrane potential, threshold potential, depolarization and hyperpolarization. (2 points) D) Indicate when voltage gated sodium channels open. Does sodium flow into or out of the cell? (1 point) E) Indicate when voltage gated potassium channels open. Does potassium flow into or out of the cells? (1 point) F) What event causes the propagation of an action potential to only occur in one direction? (1 point) 6 Name: 13) What two different roles does calcium play in neuromuscular activation and contraction? (4 points) 14)Draw and label a diagram that shows how the stretch of a muscle causes a reflex to activate contraction of the muscle to resist being stretched. (5 points) 7 Name: 15)Define a motor unit. Describe how motor unit recruitment of limb muscles changes when a person (a) is standing at rest, (b) begins walking, and then (c) (realizing that they are late) sprints to attend an important class! In your answer relate the recruitment to changes in the force and speed of movement the muscles must produce. (5 points) 8 ...
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- Fall '10
- blastocyst stage, muscle causes, embryonic development