Skin

Skin Facts

SPF= Sun Protection Factor

SPF 15- means if you burn in the sun after 10 minutes, then with the SPF 15, you can stay in the sun 150 times longer (10 X 15= 150) before burning. 

·        SPF 15 filters about 93% of the sunlight.

·        SPF 30 filters about 97% of sunlight.  (30 is not twice as strong as 15!)

·        http://skincancerstage.laughlin.com/prevention/sun-protection/sunscreen/sunscreens-explained

UVA vs UVB-

http://www.skincancer.org/prevention/uva-and-uvb/understanding-uva-and-uvb

          UVA= Long light waves—responsible for wrinkles

          UVB= Short light waves—responsible for tanning/burns

UV light is the main cause of non-melanoma cancers!!

Wrinkles:

·         Skin ages all over the body, but much more so where there has been sun exposure. Changes brought on by sun damage (photoaging) include "dryness" (really roughness), sagginess, skin growths like keratoses ("liver spots"), and wrinkles.

·         Wrinkles in turn can be divided into two categories; fine surface lines and deep furrows. Wrinkle treatments are in general much more effective for fine lines. Deeper creases may require more aggressive techniques, such as plastic surgery.

·         Factors that promote wrinkling include smoking; skin type (people with light-colored skin and blue eyes are more susceptible to sun damage); heredity (some families wrinkle more); hairstyle (depending on how much skin is covered by hair and protected from the sun); dress (again, by determining which skin is exposed); and occupational and recreational sun exposure over the course of many years.

·         Treatments available for wrinkles include medical treatments (such as vitamin A acid, alpha hydroxy acids, antioxidants, and moisturizer) and cosmetic procedures (such as glycolic acids peels, deep peels, dermabrasion, laser resurfacing, surgical procedures, and Botox).

·         The number of epidermal cells decreases by 10% per decade and they divide more slowly as we age making the skin less able to repair itself quickly.  The epidermal cells become thinner and less sticky.

Information from: http://www.medicinenet.com/wrinkles/page2.htm#glance

·         Botox for wrinkles!- check out more information of this toxin/medicine at http://en.wikipedia.org/wiki/Botulinum_toxin

Tattoos:

Permanent insoluble ink that is placed about 1 millimeter into the dermis layer of the skin.

Check it out here:  http://health.howstuffworks.com/skin-care/beauty/skin-and-lifestyle/tattoo.htm

Kingdom Monera: Bacteria

Basics to study tonight:


Characteristics of bacteria:
1. Single-celled
2. Prokaryotic - Have no nuclear membrane around the DNA
3. Has a cell membrane and cell wall

Bacteria love warm and moist places!

Can be found EVERYWHERE!



Reproduce by Binary Fission: Which basically means the bacteria splits into two.

Helpful (Good) Bacteria: Those found in foods like yogurt, cheese, sourdough bread :)
Harmful (Bad) Bacteria:  Those that make you sick like food poisoning and strep throat

More to come in class tomorrow!

Extra Credit Opportunity!

    Biology Related News Article

8 Points Extra Credit!!

Due Date: December 16^th

Goal:

1.     Find a news article (newspaper, magazine, online)

2.    Read it

3.    Highlight important/interesting information

4.    Write a short summary of article

5.    Write how the article relates to biology

6.    Staple the article to your paper

7.    Turn in to Mrs. Dokken J

Blood Genetics Tutorial

Be sure to do the "assignment" at the end of the screencast! :)

Mitosis

Make sure you understand the phases of Mitosis for tomorrow's class!  

This is an animal cell undergoing mitosis like we discussed in class today. Mitosis is when a cell divides into two and FORMS TWO EXACT NUCLEI.  After the nuclei are formed, the rest of the cell splits (the cytoplasm and cell structures are divided up) through "CYTOKINESIS" (important term).  Remember, most of the time, a cell is in Interphase doing normal cell functions (also growing and duplicating it's DNA).  But, when it's time to divide it begins the process of Mitosis as shown here:



Image taken from: accessexcellence.org


Plant cells also undergo mitosis, but it is different because the plant cell forms a "cell plate" instead of undergoing cytokinesis!


On Thursday in class you will be looking at Onion Plant Cells going through Mitosis. You will have to identify three different stages for a lab grade.  If you can correctly point all FIVE phases of Mitosis, you can count that towards 10 points of your cell project part B! :)


Here are some examples of what you might see:

Image take from: faculty.cbu.ca


We talked in class about how you have mitosis going on in your body cells all the time.  That is a good form of mitosis, but mitosis can be bad if a "bad" cancer cell is undergoing mitosis.  The definition of cancer is "a disease in which some cells in the body divide uncontrollably."  

Cells: Structure and Function

Hopefully, your cell project is going well and you are starting to "get it".  Cells really are similar to a city with many different jobs that have to be done.  Cells are just smaller and have organelles instead!  If you had to compare them, you could say the nucleus is like the "mayor" or "boss" of the city,  the lysosomes are like the "trash collectors", the endoplasmic reticulum is the "highway", etc.  Tomorrow is our quiz.  Here is a good website to use to study...http://www.neok12.com/Cell-Structures.htm  We did some of these quizzes in class.  I think you'll find them helpful!

Using the Scientific Method

How does temperature affect the growth rate of sponge critters?  We're about to find out!