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Virtual Restriction Enzyme Lab

Calorie restriction has long been studied as a way to extend lifespan in animals. It has been associated with the ability to reduce the risks of cardiovascular and other diseases and to improve overall health. Now, researchers at Chang Gung University in Taiwan have found that calorie restriction can ...

1:30 animation As a human embryo develops, its cells become progressively restricted in the types of specialized cells that they can produce. Inner cell mass (ICM) cells of the blastocyst can make any type of body cell. Gastrula-stage cells can give rise to the cells of a given germ layer. Later, cells become even more restricted. For example, the pancreatic bud of the endoderm layer can only make the cells of the pancreas.

Paul Andersen explains the two major portions of the molecular biology lab in AP Biology. He starts by discussing the process of transformation. He explains how you can use the pGLO plasmid to produce glowing E. coli bacteria. He then describes how you can use restriction enzymes and the process of gel electrophoresis to cut and separate DNA.

To understand the importance of elements to nutrition. Of the approximately 115 elements known, only the 19 highlighted in purple in Figure 1.26 are absolutely required in the human diet. These elements-called essential elements-are restricted to the first four rows of the periodic table (see Chapter 32 "Appendix H: Periodic Table of Elements"), with only two or three exceptions (molybdenum, iodine, and possibly tin in the fifth row). Some other elements are essential for specific organisms. For example, boron is required for the growth of certain plants, bromine is widely distributed in marine organisms, and tungsten is necessary for some microorganisms.

Such descriptions of GMOs raises fears about whether gene transfer between species is outside of how evolution operates and therefore unnatural. Research, however, has repeatedly shown the opposite to be true. In May 2015, researchers showed that practically every known species of cassava (sweet potato) contained genes from Agrobacterium, a bacterial species whose genes we have also harnessed to create other GM crops. The genes were inserted over 8,000 years ago and may have helped the tuber evolve into its current, edible form. This phenomenon of genetic transfer during evolution between species, also known as 'horizontal gene transfer' is not restricted to plants.

But scientists from the University of Southern California showed that, in mice, the Fasting Mimicking Diet (FMD) significantly lowered the percentage of damaging immune cells, while allowing the protective coating to regrow.

1 min animation clearly showing digest

2:18 Human embryonic development depends on stem cells. During the course of development, cells divide, migrate, and specialize. Early in development, a group of cells called the inner cell mass (ICM) forms. These cells are able to produce all the tissues of the body. Later in development, during gastrulation, the three germ layers form, and most cells become more restricted in the types of cells that they can produce.

Existing mouse models of lethal Ebola virus infection do not reproduce hallmark symptoms of Ebola hemorrhagic fever, neither delayed blood coagulation and disseminated intravascular coagulation, nor death from shock, thus restricting pathogenesis studies to non-human primates. Here we show that mice from the Collaborative Cross exhibit distinct disease phenotypes following mouse-adapted Ebola virus infection. Phenotypes range from complete resistance to lethal disease to severe hemorrhagic fever characterized by prolonged coagulation times and 100% mortality. Inflammatory signaling was associated with vascular permeability and endothelial activation, and resistance to lethal infection arose by induction of lymphocyte differentiation and cellular adhesion, likely mediated by the susceptibility allele Tek. These data indicate that genetic background determines susceptibility to Ebola hemorrhagic fever.

2 min video A quick tutorial, showing how we use restriction enzymes to cut out a desired gene from one organism, and insert it into the plasmid of a bacterium. This allows massive production of the desired protein (in this case the hormone: insulin) in a relatively short amount of time.

Gene flow is the transfer of genetic material between separate populations. Many organisms are divided into separate populations that have restricted contact with each other, possibly leading to reproductive isolation. Many things can fragment a species into a collection of isolated populations. For example, a treacherous mountain pass may cut off one herd of mountain goats from another. In human beings, cultural differences as well as geographic separation maintain unique populations: It is more likely that a person will marry and have children with someone who lives nearby and speaks the same language.

Explore electrophoresis with The Amoeba Sisters! This biotechnology video introduces gel electrophoresis and how it functions to separate molecules by size. Restriction enzymes, DNA ladders, and DNA fingerprinting briefly introduced.

Alternative labs list- AP biology teachers submit a curriculum for review and approval and must include laboratory exercises that align with their core ideas. Some of the recommended labs may be too expensive or too time consuming for your class. Listed below are some alternatives that may be acceptable as part of your overall biology curriculum.

Resource rich site for Regent's Biology and AP Biology

activities

"CRACKING THE CODE"/"Cloning Paper Plasmid" activities can (1) serve as a review of the "genetic code" and the role it plays in our life; and, (2) to help students see how genes may be manipulated for genetic research, namely, gene cloning/genetic engineering. The laboratory time, the specialized equipment and expertise to carry out recombinant DNA experiments may be lacking in the high school. Activity 2 will help students conceptualize the mechanics involved in cutting and ligating DNAs into a plasmid vector with "sticky ends" of complementary DNA base pairs.

Paper Cloning activity with worksheet questions

But did they actually live longer? The answer is yes! The average lifespan of monkeys on a regular diet is approximately 26 years, but the CR monkeys lived on average 3 years longer, a whopping 10 percent increase. The statistics suggest at any point in time, the control monkeys had 2.9 times the rate of death from age-related causes compared to those on a CR diet.

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