How does myosin generate force for muscle contraction? A. Titan regulates the length of the thick and thin filaments. B. Hydrolysis of ATP promotes a conformational change in myosin. C. Ca2+ release from the sarcoplasmic reticulum promotes tropomyosin binding to the thick filament, inducing a conformational change in myosin. D. The extended coiled coil tail of myosin wraps around actin. E. Myosin binds to the Z-disk to bring the M-line closer to the A-band.

In gymnosperms, the food source for the embryo in the seed is megagametophyte tissue. This tissue is present before the egg is produced and certainly before an embryo is formed. In flowering plants, the main food source for the embryo in the seed is the endosperm. Endosperm has some benefits over gametophyte tissue as a way to store food in a seed because O it is typically triploid rather than haploid. it can be produced in greater quantity. it is not produced unless an embryo is already developing. it has greater genetic diversity than gametophyte tissue. Is it possible for a flower to be perfect and incomplete? ○ Yes, flowers can be perfect or incomplete. No, but they can be imperfect and complete O No, if a flower is perfect it must be complete. Question 9 In a typical plant, one megaspore survives and then goes on to produce the embryo sac. It turns out that in Lilium (and some other plants) all four megaspores survive. It works like this: A diploid cell (megasporocyte) goes through meiosis to produce 4 megaspores. Three of the megaspores fuse to form a triploid nucleus. The haploid and triploid nuclei each go through two rounds of mitosis to produce 8 nuclei. The antipodal cells are each triploid. The synergids and egg cells are haploid. After fertilization, what would the ploidy of the endosperm be? Diploid Triploid ○ Tetraploid Pentaploid Hexaploid

Briefly explain why the relationship between genotype and phenotype is often complex for quantitative traits

Write a paper on a genetic disorder of your choice (There will be a signup list). There is a list of disorders that you may consider covering at the bottom of this document. You may cover a disorder not included in the list, but you need to discuss the disorder you wish to cover with your instructor first to make sure it will be appropriate for the project.

Include the following:

1. Discuss a genetic disorder and how it is passed down from generation to generation.
2. The name of your genetic disorder
3. Pattern of inheritance – Is this disorder dominant/recessive/sex-linked/autosomal?
4. Give the genetic disorder’s genotype. Example: Trisomony on the 21st chromosome.
5. List the symptoms and what happens to you if you have this genetic disorder?
6. The phenotype of the disorder.
7. Describe the defect that the disorder causes.
8. Is there now, or was there ever a benefit to this genetic disorder?
9. What may cause this genetic disorder? Mutation, radiation, etc.
10. Is there any treatment or cures or light altering measures for this genetic disorder? Ex: special diets, medications, exercise – to survive this condition?
11. Are certain people more likely to produce children with this genetic disorder?
12. Frequency among human births.