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Based on what you know about the likely content(s) of the contraceptive birth control pill, briefly explain how it regulates ovulation (or lack thereof) by a negative feedback process.

Using the letters corresponding to the stages in the physiology of muscle contraction, write the events of muscle contraction in chronological order in the space provided. Note:  The first step begins somewhere in the neuron as I want to determine if you still understand some of the steps that take place in the neuron from previous notes.     a. Attachment of another ATP allows the cross bridge to detach from the actin and repeat the cycle over  again as long as Ca2+ remains attached to troponin.    b. Voltage-gated Ca2+ channels open in pre-synaptic terminal and Ca2+ enters cell.    c. Ca2+ attaches to troponin, causing a conformational change in its structure.     d. Action potentials in the T tubule stimulate the release of Ca2+ from the terminal cisternae.    e. ACh diffuses across cleft and binds to ACh receptors.     f. Action potentials stop being produced, SR accumulates calcium and the troponin-tropomyosin complex moves again to its inhibitory position.    g. Binding of ACh to receptors opens up ion channels on muscle cell membrane that causes EPP’s and a      depolarization of the muscle.    h. Myosin cross-bridges bind ATP, attach to actin, and undergo a power stroke.      i. Action potentials are conducted in a motor neuron and arrive at the terminal of the axon.     j. Shape change in troponin causes tropomyosin to shift position in the actin filament, thus exposing binding sites for the myosin cross-bridges.    k. T tubules conduct action potentials deep into the muscle fiber.    l. Ca2+ entry causes the release of ACh at the neuromuscular junction.  m. Action potentials are conducted across the muscle cell membrane.

Conversion of the “indifferent” gonad into a testis depends on the presence of the _________.

Which of the following is false regarding the follicular phase?    a. It occurs from ovulation to the first day of the next menstrual cycle.    b. Ovarian follicles begin to grow during this phase.    c. It includes the menstrual phase.    d. It includes the proliferative phase of the cycle.    e. Progesterone concentrations are low in this phase.

In which skeletal muscle band are no thin filaments typically found? You can just write the letter of the band.  __________

Which chemical causes an inhibition of the release of ACh?    a. Curare    b. Black widow spider toxin    c. Botulinum toxin    d. Nerve gas    e. Some pesticides

During a specific time of the menstrual cycle, both a steroid hormone and the gonadotropins increase at about the same time.  Of what phenomenon is this an example? ____________

All of the following can be used to describe the length-tension relationship for skeletal muscle except:    a. It exhibits an optimal muscle length for tension generation.    b. It can be explained using the sliding filament mechanism.    c. At lengths less than optimal the tension generated is reduced.    d. At lengths greater than optimal the tension generated is greatest.    e. All of those mentioned are true.

Write out the HPG axis for the human female specifically. Include all relevant anatomical structures, all relevant hormones involved.  Spell out all hormones in the axis.  You can write the axis as a flow chart if you would like.  Also, write out one example of a long negative feedback loop and one example of an ultra-short negative feedback loop.  For the feedback loops, just state which specific hormone feeds back to which specific gland. 

Fill in the following:     Stimulus: _______ (Remember to say if the stimulus is increased or decreased)     Endocrine gland activated: _______      Hormone released: _______     Target organ(s) affected: _______     Response:  Increased reabsorption of sodium