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Our team of scientists documented that more than 300 camels in the region around Dubai had died from eating humans' trash, accounting for 1 percent of dead camels evaluated in the region since 2008. Unlike other research that might examine animals in a laboratory, this was a field study with concentrations of plastic trash that currently exist in the environment. It is a real-world tragedy with ecologically relevant concentrations of trash.

Reference page cellular facts: cell size, lenth, division, concentration, energy, diffusion, genomic information, and mutation rates.

In this video Paul Andersen details the action potential in neurons. The resting potential of a neuron (-70mV) is maintained through differences in concentration and permeability of Na, K, and Cl ions. A graded potential is created as neurotransmitters from adjacent cells that are either excitatory or inhibitory. If the neuron reaches the threshold of -55mV an opening of voltage-gated sodium channels triggers an action potential

An overview of the immune system, concentrating on the roles played by B and T lymphocytes, and the antigen-presentation system.

Movement of ions in and out of cells is crucial to maintaining homeostasis within the body and ensuring that biological functions run properly. The natural movement of molecules due to collisions is called diffusion. Several factors affect diffusion rate: concentration, surface area, and molecular pumps. This activity demonstrates diffusion, osmosis, and active transport through 12 interactive models. Start by following the path of a molecule of dye in water, create concentration gradients on either side of a cell membrane and watch the movement of substances in and out of a cell, and monitor the movement of oxygen into red blood cells with and without hemoglobin.

Awesome interactive player

When researchers tested wastewater before and after treatment at a Milwaukee-area treatment plant, they found that two drugs-the anti-epileptic carbamazepine and antibiotic ofloxacin-came out at higher concentrations than they went in. The study suggests the microbes that clean our water may also piece some pharmaceuticals back together.

Mathematician-turned biologist Dr. Corina Tarnita describes the importance of termite mounds in a savanna ecosystem. Termite mounds are biological hotspots that concentrate nutrients and water in semi-arid savanna ecosystems. When viewed from above, the mounds form a strikingly regular polka-dot pattern. Dr. Corina Tarnita uses mathematical modeling to explain the regularity of the pattern, how it arises, and how the mounds enhance the stability of the ecosystem.

What an incredible transformation. A protein used to help bones mend can also force pancreatic cells into producing insulin. The discovery could help people with type 1 diabetes produce their own insulin without having to take daily injections. In type 1 diabetes, beta cells in the pancreas that make insulin - the hormone that keeps our blood glucose levels at a safe concentration - are destroyed by the immune system. As a result, people with the disease have to inject themselves daily with insulin. Now, researchers have discovered that non-beta cells in the pancreas can be transformed into insulin-producing cells, merely by exposing them to a growth factor called BMP-7.

The human large intestine (colon), in healthy individuals, has extremely low oxygen concentrations, and over 90% of its microbiota are strict anaerobes. Researchers taking metagenomic fecal microbiota surveys of adult Europeans could assign about 0.8% of the genes in their dataset to archaea [9], and similar numbers (0.2%-0.3%) were reported for Amerindians and Malwaians [10], while North Americans had much lower fractions (<0.05%).

The following has been excerpted from a very popular Worthington publication which was originally published in 1972 as the Manual of Clinical Enzyme Measurements. While some of the presentation may seem somewhat dated, the basic concepts are still helpful for researchers who must use enzymes but who have little background in enzymology.

In this interrupted case study developed for use in a flipped classroom, students read about a picnic that takes place in autumn during the peak of fall color and along the way learn about light absorption by photosynthetic pigments, why leaves turn color in the fall, atmospheric CO2 concentrations and their effect on photosynthesis, and the C3, C4, and CAM photosynthetic pathways. The case is designed to provide introductory biology students with a basic understanding of photosynthetic pathways and how environmental factors affect plants using these pathways. The activity could also be used in an advanced high school biology course covering photosynthesis. The case includes several short videos that students watch as homework before coming to class so that they are prepared to work together in class in small groups to answer the case questions.

For this third episode of our video series with Vox's Future Perfect team, we went to North Carolina, a state that's been battling the public health and environmental impact of hog lagoons for decades. The issue is especially grave in this state due to the vulnerable populations who bear the brunt of this pollution, and because hog facilities are so concentrated in such a small area.

Interactive activities