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From single-celled organisms to giant redwoods, Life Science explores all of Earth's life forms. Use interactive, animated activities to identify the living and nonliving components of an ecosystem, design a Venn diagram to compare the migrations of monarch butterflies and red knot shorebirds, and take a virtual field trip to a solar farm. Resources in Life Science gives you a wide range of topics, including the cell cycle, genetic disorders, and bioethics.

The cellular life cycle, also called the cell cycle, includes many processes necessary for successful self-replication. Beyond carrying out the tasks of routine metabolism, the cell must duplicate its components - most importantly, its genome - so that it can physically split into two complete daughter cells. The cell must also pass through a series of checkpoints that ensure conditions are favorable for division.

4:17 video malaria life cycle

This interactive activity adapted from the University of Alberta illustrates how, through a process called fixation, nitrogen flows from the atmosphere, into the soil, through various organisms, and back to the atmosphere in a continuous cycle.

JoAnn Burkholder and her associates at North Carolina State University were the pioneer investigators in the Pfiesteria research, which our group of Old Dominion colleagues has since pursued. Burkholder was the first scientist to link the 1991 fish deaths to Pfiesteria, based on her team's on-site investigations and controlled laboratory studies. In addition, she observed a complicated life cycle in the organism, including numerous morphological forms such as motile flagellated cells, amoebae and cysts that are able to survive in the sediment of estuaries until activated by the presence of fish to produce toxic motile cells. 

The life science/biology course is divided into 12 instructional segments grouped into four sections. In the first section, From Molecules to Organisms: Structures and Processes, students develop models of how molecules combine to build cells and organisms (IS1 [Structure and Function]; IS2 [Growth and Development of Organisms]; IS3 [Organization for Matter and Energy Flow in Organisms]). In the second section, Ecosystems: Interactions, Energy, and Dynamics, students zoom out to the macroscopic scale to show how organisms interact (IS4 [Interdependent Relationships in Ecosystems]; IS5 [Cycles of Matter and Energy Transfer in Ecosystems]; IS6 [Ecosystem Dynamics, Functioning, and Resilience]; IS7 [Social Interactions and Group Behavior]). Students return to the role that DNA plays in inheritance during the third section, Heredity: Inheritance and Variation of Traits (IS8 [Inheritance of Traits]; IS9 [Variation of Traits]). The class ends tying together interactions at all these scales by explaining evolution and natural selection in Biological Evolution: Unity and Diversity (IS10 [Evidence of Common Ancestry and Diversity]; IS11 [Natural Selection]; IS12 [Adaptation and Biodiversity]). A vignette in IS12 illustrates the level of three-dimensional understanding students are expected to exhibit as a capstone of the course.

This case study was inspired by the Zika virus outbreak that occurred around the time of the 2016 Olympic Games. Many athletes were fearful of attending because of the link between Zika virus infection and microcephaly in infants. This concern, however, ran contrary to reports suggesting that the risk of athletes and other travelers becoming infected was remarkably low. Jessica, a fictional Olympic equestrian and the main character of the case, was unfortunately very unlucky and contracted Zika virus near the time of the Games. She ended up enduring negative health complications likely as a consequence of the infection.  This case was designed to be implemented in the nervous system unit of a human biology or anatomy and physiology course. The case is also appropriate for microbiology and public health courses.   Students are expected to have foundational knowledge in viral life cycles, and will explore disruptions in neurotransmission as well as abnormal fetal brain development.

Why is the North American population of monarch butterflies declining? In 1999, a study published in the journal Nature suggested that a variety of genetically modified corn was killing these iconic butterflies. While it was later shown that the conditions in this study did not mirror those in the field, the results garnered a lot of media attention and many people today still believe that monarchs are being killed by GMOs. This case familiarizes students with the plight of the monarchs, encourages them to think about how to test the hypothesis that a toxin is responsible for their decline, and takes a critical look at several studies that investigated the role of Bt corn in the life cycle of monarchs. This interrupted case takes 60-90 min to complete, requires little to no science background, and can be used to explore the ecology and wildlife management of monarchs; risk assessment, toxicity, and exposure; experimental design, the scientific method, hypothesis, and critical thinking; or the relationship between science, the media and the public.

Before civilization began to impact the human life cycle approximately 10,000 years ago, human beings had high birth and death rates. Today the world is in the midst of a demographic transition - a transition to low birth and death rates - as the ability to control both disease and reproduction increases. Along the way, between these extremes, populations go through an intermediate period of continued high birth rates, combined with low death rates, resulting in a population explosion.

Life on Earth is intimately connected to the natural cycles of light and dark that make up a 24-hour day. For plants, animals, and even bacteria, these circadian rhythms control many biological functions. Humans can overrule their body clocks, but at a price: People whose circadian rhythms are regularly disrupted-by frequent jet lag or shift work, for example-are more vulnerable to diabetes, obesity, cardiovascular disease, and cancer. There are various theories to explain these associations, and researchers now have a new player to consider: the bacteria that live in the digestive tract. According to a study in mice and a small group of human volunteers, the internal clocks of these gut microbes sync up with the clocks of their hosts. When our circadian rhythms get out of whack, so do those of our bacteria.

This case study follows two beginning undergraduate researchers on a quest for a summer research project related to food web ecology. While writing their research proposal, the students receive feedback indicating that they have neglected an entire group of organisms from their food web-parasites, which leads them to a scientific research paper discussing how these organisms have been overlooked by scientists studying food webs, the challenges involved with including parasites in food webs, and the contributions parasites ultimately make to food webs. An integrated activity in which students visualize the food web using images of organisms and answer questions about species interactions provides opportunities to examine key concepts such as omnivory, ontogenetic diet changes, trophic levels, complex life cycles, and taxonomic aggregation. This case study was originally written for an undergraduate general ecology course, but could easily be adapted to undergraduate general biology courses covering community ecology or specific courses in invertebrate zoology, parasitology, or disease ecology. The teaching notes also discuss how the included code for R statistical computing software can be used to extend the case study in a more quantitative direction if desired.

The online textbook provides a background to understand and discuss the natural functioning of the different Earth systems; it introduces humans as part of the overall ecosystem and explores what is needed to sustain human life; and it looks at the effects that human actions have on different natural systems. The online textbook also includes full-color images of related figures, glossary terms, and a bibliography for further reading.

Reference site for International Baccalaureate (IB) Biology course.

Extensive lessons from hands on inquiry lab at University of Rochester, developed/written with research funds.

Earlier this week, the space agency released a new simulation created with this model, called GEOS-5, that shows clouds of carbon dioxide, a key driver of global warming, drifting far from their original sources - turning local greenhouse gases into global problems.

animation of influenza infection