For the experiment below, describe it as correlation, loss-of-function or gain-of function. Then, indicate the predicted result.

The purple sea urchin (Strongylocentrotus purpuratus) and a sympatric species known as the red sea urchin (Strongylocentrotus franciscanus) release their gametes into the Pacific Ocean at the same time, but the sperm cells of each species fail to fertilize the egg cells of the other species due to different membrane proteins. This prevention of interspecific fertilization in sea urchins is:  a post-zygotic barrier known as F1 hybrid inviability a pre-zygotic barrier known as habitat isolation a post-zygotic barrier known as F1 hybrid sterility a pre-zygotic barrier known as gamete isolation a pre-zygotic barrier known as temporal isolation

Background: The slow block to polyspermy involves a permanent modification of the egg surface, usually through exocytosis of the cortical granules. In the 1970s, Dave Epel carried out experiments that led to the conclusion that a Ca2+ rise in the egg is both necessary and sufficient to trigger cortical granule exoctyosis (CGE).       Experiment (c) – Dr. Epel injects a calcium chelator (called EGTA; chelators act as specific “sinks” or “magnets” for ions) into unfertilized eggs and then adds sperm. The sperm bind and fuse with the eggs, but no CGE occurs.   For the experiment above, describe it as correlation, loss-of-function or gain-of function. Then, indicate the predicted result.

a. Each person inherits one copy of the Huntington's Disease gene from each parent. Explain why the negative control sample (from an unaffected individual) only produced one band.   b. Explain why the positive control sample (from an individual affected by Huntington’s disease) produced twobands.

Propose an experiment and suggest a control treatment for each of the following questions.  Do bearded dragons that are genetically male chnage into females if eggs are incubated at temperatures above 32 C?

Describe the dorsolateral and ventrolateral migration of trunk neural crest cells. Provide details as to the timing of the migration, pathways taken, eventual fate, and location of the neural crest cells that follow each pathway or portion of the pathways. Include a simple drawing that depicts both pathways .

Discuss and compare the source (mechanism) and types of increased mutations in older mother oocytes versus older father sperm (ch 4 and ch 7.) (Diagrams may be helpful if needed to convey your thoughts

The chemotherapy agent, Tamoxifen, is effective at blocking the ability of estrogen to stimulate cell division. Where does Tamoxifen bind to influence this response? O to the estrogen receptor O to estrogen response elements O to the promoter region of estrogen responsive genes O to estrogen activator proteins

Chorionic villus sampling (CVS) is used to test for genetic disorders in the fetus and can be performed early in gestation (8-10 wks). The recommended method of CVS is to sert a probe with a needle on the end through the cervix and remove a small sample of e chorionic villi to be analyzed. Which description is a correct description of chorionic villi? Select one: They are found in the digestive tract of the fetus. They are developed from the endometrium. They contain cells whose nuclei differ genetically from cells of the fetus. They form part of the placenta.

The amount of DNA in a differentiating oligodendrocyte in M-phase is 210pg. How much DNA would be present in Go? Briefly describe the expected cellular function during this stage How much DNA would be present in G₂? Briefly describe the expected cellular function during this stage. What is the number of chromosomes during gametogenesis if you have eight chromosomes at Meiosis I? What is the amount of DNA in a spermatozoa cell? a. 1x b. 0.5X C. 2X d. 0.25X 688 words IX English (United States) Focus. E