I) The importance of aseptic techniques in a Microbiology lab. 2) Aseptic technique procedures. 3) Aseptic transfer of live cultures from Broth to slant Slant to broth. a. b. KEY WORDS Aseptic technique Sterilization Disinfection Pure culture Inoculation loop Inoculum Sediment Turbidity Sepsis Degerming AutoclaveSlant culture cultureTurbidity Aerosolization Pellicle INTRODUCTION Importance of aseptie techniques As seen in the previous lab, bacteria are ubiquitous! The term sepsis is used when microbial growth is present in places where it is not supposed to be present. Usually used for infected tissue. Therefore, when working with microorganisms, it is important that we prevent contamination of our cultures with other microorganisms from the environment. The techniques used to prevent contamination from occurring are known as aseptic techniques. Applying these techniques is important in obtaining and maintaining pure cultures (cultures that contain only one type of organism). The proper use of these techniques will also protect you and your classmates from exposure to the bacteria cultures we are working with. To prevent contamination we will be working with sterile media. This means that they do not contain any microorganisms including viruses or spores that may be more difficult to kill. Special techniques such as autoclaving are used during their preparation. The autoclave is similar to a pressure cooker, it uses steam under pressure to denature the proteins of organisms in order to achieve sterilization. The major tool of the microbiology lab is the inoculating loop; we will be using a Bunsen burner to sterilize it before and after each use. Because microorgan not be able to totally eliminate them; but we do want to decrease their presence. One of the ways eliminate all bacteria, but decreases their numbers. Washing your hands is also important. There are many resident bacteria that live on your hands. Touching contaminated surfaces picks up transient bacteria. Washing will decrease the numbers of bacteria but does not eliminate them (the residents are especially hard to remove). This process is known as degerming. isms are everywhere in our environment, including all over us, we will we will do this is by disinfecting our lab surfaces with bleach. Disinfection does not 25

What is the osmolarity of the following solution?

1M glucose, 2M NaCL

Don’t include units in your answer.

Measurements of lifetime reproductive success (LRS) of individual wild animals reveal the disparate contributions they make to the next generation. Jensen et al. (2004) estimated LRS of male and female house sparrows in an island population in Norway. They measured LRS of an individual as the total number of “recruits” produced in its lifetime, where a recruit is an offspring that survives to breed one year after birth. Parentage of recruits was determined from blood samples using DNA techniques. Their results are tabulated as follows: ea In th th 0 Lifetime reproductive success Frequency Females Males 30 25 38 17 10 22. A dit fer ag les se ber >8 81 84 Total a. Which sex has the higher mean lifetime reproductive success? 12.7