Lamellar corpuscle 7. Hypodermis 8. Dermis 9. Epidermis 10. Tachtile corpuscle 11. Dermal papilla 12. Sweat pores Questions A. How does the skin tan when exposed to ultraviolet light? Melamin synthesis are stimulated by the UV light which darkens the skin. B. Describe the functions of the epidermis. The epidermis is the outermost layer of the skin. This layer of skin acts as a barrier to help protect the body from the environment. C. Describe the
Premium Skin Epidermis
protectant levels to protect bacteria from ultra-violet (UV) light Ben Mitchell‚ Brigette Geniusz‚ Tylor Holcomb‚ Mark Kendrick June 16‚ 2014 Abstract: The efficacy of sunscreen is important because it blocks potentially harmful UV light‚ which may be a primary factor in skin cancer. Different levels of sun screen were tested alongside lotion and no treatment to see how well they protected Escherichia coli strain K-12 (Ecoli K-12) from UV light. The group that was treated with the strongest level
Premium Ultraviolet Sunscreen
Since the Grignard reagent can easily react with water‚ all glassware including the 25 ml round bottom flask‚ magnetic stir bar‚ 3 and 5 ml conical vial‚ 50 mL Erlenmeyer flask‚ claisen adapter‚ drying tube and 5 glass pasteur pipets were first added to a 250mL beaker and placed in the oven for 30 minutes. After the completion of the thirty minutes‚ 0.150 g of shiny magnesium turnings and a stir bar was first added to the round bottom flask and the claisen adapter along with the drying tube packed
Premium Chemistry Water Solvent
Purpose: To find out the densities and to find out the name of the unknown metals. (Based on the extensive and intensive properties) Check up the words mass‚ volume‚ density‚ extensive properties‚ and intensive properties. Where do the units for mass and volume) come from and what do they mean? What is the density of distilled water? What is Archimedes principle? Does temperature affect the density of a solid? Liquid? Gas? Materials: Safety glasses‚ 10‚ 25 or 50 mL graduated cylinders
Premium Water Liquid Density
Briefing Thin-layer chromatography (TLC) is an extremely valuable analytical technique. It provides a rapid separation of compounds‚ and gives an indication of the number and nature of the components of a mixture. TLC can also be used to identify compounds by comparison with known samples‚ to check the purity of a compound‚ or to monitor the progress of a reaction‚ an extraction‚ or a purification procedure. This experiment will introduce you to the mechanics of TLC‚ and the chemical principles
Premium Thin layer chromatography Chromatography Solvent
Microscopes are designed to view objects that are too small to see with naked eyes. The different kinds of microscopes include; phase-contrast‚ dark-field‚ polarizing and UV. Each of these microscopes differs in the source and manner in which the light is passed through the specimen to be viewed. The microscopes that are usually used in biology labs are compound binocular or monocular light microscopes. Compound microscopes have a minimum of two magnifying lenses (ocular and objective). Binocular microscopes
Premium Blood Leaf Lens
Column and thin layer chromatography of plant pigments CHEMISTRY 201L EXPT 04 PAGE 01 - 12 Noel Angelo P. Kalacas*‚ Hanna Mae Laluces‚ Ina Bianca Lanuza Department of Chemistry‚ College of Science *Corresponding author; e-mail: knight_BeNcH66@yahoo.com Abstract Chromatography is a powerful technique for separating and/or identifying the components in a mixture. There are different types of chromatography and each has its own strengths and weaknesses. In this experiment‚ pigments of the
Free Chromatography Thin layer chromatography
dependent on the large‚ free living sporophyte. One advantage of this is that the delicate female gametophytes do not have to cope with environmental stressors - female gametophytes and the embryos they produce are sheltered from drought and harmful UV radiation by their enclosure within the moist reproductive tissues of the parental sporophyte generation. Nutrient exchange also occurs between gametophytes and their parents. In contrast‚ the free-living gametophytes of seedless vascular plants must
Premium Seed Plant Flower
African Diaspora and the World After reading the short story “Diaspora” by Joanne Hyppolite‚ I got a vivid understanding of how diaspora can have an effect on one’s identity. Over the past month we have studied many theories and concepts concerning race‚ gender‚ and politics. There are three theories that capture the essence of Joanne Hyppolite’s worldview as a Haitian growing up in America: intersectionality‚ identity‚ and diaspora. Individuals oftentimes experience the theory of Intersectionality
Premium African American Race Black people
Alyssa Caparelli Organic Chemistry 12A Professor Alston October 28‚ 2014 Isolation of Chlorophyll and Carotenoid Pigments from Spinach Purpose The purpose of this experiment was to isolate ß-carotene‚ chlorophyll-A‚ and chlorophyll-B from spinach using column chromatography. Spinach was dehydrated using ethanol‚ and the pigments were extracted with dichloromethane. The spinach extracts were dried using CaCl2. Then‚ the solid pigments were run through a column using a non-polar solvent‚ hexane
Free Solvent Acetic acid Ethanol