Science Homework Help

Part I. Microscopy Image labelinga.You have been given a set of microscopy images that are different from the others in your group that encompass gametogenesis (mammalian), fertilization and cleavage (for echinoderms and amphibians). 1. Examine all your images within PowerPt and label them with appropriate structures and stages. You will be using these same slides for your lab report and incorporating them into your discussion of early development so make sure to save this file.Terms that may be in your images: – Primary/secondary/tertiary ovarian follicles (one or more types may be observed); – Zona pellucida/Vitelline envelope (and Fertilization envelope for sea urchins), egg jelly– Germinal vesicle, nucleolus, nucleus, polar body, pronuclei– Granulosa cells, basal lamina, antral cavity, seminiferous tubule, spermatogonia, primary spermatocyte, secondary spermatocyte, spermatid, sperm, acrosome (general location for it), sperm flagellum– Cleavage stages (2-, 4-, 8-cell, or if more than 8 you can state mid-late cleavage stage), Animal/Vegetal pole or hemisphere2. Present your slides to your group members and discuss them (as to accuracy and whether anything relevant is missing).Part II. General questions to answer:1. How do you know you are looking at a germinal vesicle (describe/explain)? What is the genetic state of the germinal vesicle (how much DNA is in this compartment)?2. How can you tell the difference between a primary, secondary and a tertiary ovarian follicle? (what are the hallmarks)3. How would you distinguish the mature sperm from a secondary spermatocyte? What meiotic stage would each be in (4n, 2n, n)?

How can you tell the difference between a fertilized sea urchin egg from one that is unfertilized (describe)?5. How can you tell the difference between the animal versus the vegetal pole (hemisphere) in amphibian eggs that are fertilized and undergoing cleavage.