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Group Behavior - Student Protocol

JoVE 10612

The Hawk-Dove Game
NOTE: In this activity, you will play the hawk and dove game with a single partner and then with multiple partners to observe hypothetical costs and benefits of the antagonist or cooperative behavior respectively.
Before the activity starts, review the cost-benefit table so that you understand how to score the game. Click Here…

 Lab Bio

Microbial and Fungal Diversity - Student Protocol

JoVE 10602

Examining Microbial Colony Structures
To begin, collect your allocated culture plates and then remove the Parafilm and lid from one of them.
Place the uncovered plate under a dissecting microscope and then observe the individual communities within each quadrant of the plate.
As the colonies are identified, fill out the observed colony…

 Lab Bio

Natural Selection - Student Protocol

JoVE 10593

Simulating Natural Selection
To begin, cut the white, black, and gray pipe cleaners into quarters, which should produce a total of 100 pieces that are 3 inches long.
Then, cut the green pipe cleaners in the quantities and lengths specified in the video, taking care to minimize waste. This approximates a normal distribution of lengths and should…

 Lab Bio

DNA Isolation and Restriction Enzyme Analysis - Student Protocol

JoVE 10576

DNA Isolation
NOTE: In this experiment you will perform DNA isolation under two experimental conditions: one using a buffer containing the detergent SDS and one without detergent. Hypotheses: The alternate hypothesis for this experiment might be that the sample prepared without SDS, a strong anionic detergent that breaks apart cell membranes, will yield …

 Lab Bio

Enzyme-linked Receptors

JoVE 10723

Enzyme-linked receptors are proteins which act as both receptor and enzyme, activating multiple intracellular signals. This is a large group of receptors that include the receptor tyrosine kinase (RTK) family. Many growth factors and hormones bind to and activate the RTKs.

RTKs are also called neurotrophin (NT) receptors because they bind nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), NT-3, NT-4/5, NT-6, and NT-7. The growth factors typically bind to an RTK subfamily of tropomyosin-related kinase receptors (Trk): Trk A, Trk B, and Trk C. Trk A is specific for NGF, NT-6, and NT-7. Trk B binds BDNF and NT-4/5, while Trk C is specific for NT-3. NT-3 can also bind with low affinity to Trk A and TrkB. The Trk receptors have a single transmembrane domain, with a growth factor binding site on the extracellular portion and an enzyme activation site intracellularly. Trk receptors can be monomeric or dimerized, where two Trk receptors are bound together. To activate the receptor, a single growth factor molecule either binds two monomeric receptors, causing them to dimerize, or it binds both sites on a pre-dimerized receptor. Once the receptors are bound, the tyrosines phosphorylate by pulling phosphates from ATP and donating them to each other, a process called “autophosphorylation.” This opens docking sites along the i

 Core: Biology

Physiology of the Circulatory System - Student Protocol

JoVE 10570

Measuring Circulatory System Function in Humans
Before starting the experiment go to the front of the room and collect an alcohol swab, a sphygmomanometer, and a stethoscope.
Clean the earpieces with the alcohol swab and then insert them into your ears.
To check if the stethoscope is in the on position, gently tap the flat metal disc called…

 Lab Bio

Threats to Biodiversity

JoVE 10951

There have been five major extinction events throughout geological history, resulting in the elimination of biodiversity, followed by a rebound of species that adapted to the new conditions. In the current geological epoch, the Holocene, there is a sixth extinction event in progress. This mass extinction has been attributed to human activities and is thus provisionally called the Anthropocene. In 2019 the human population reached 7.7 billion people and is projected to comprise 10 billion by 2060. Indicative of our impact, by biomass (the actual mass of a particular species), humans make up 36% of Earth’s mammals, livestock 60%, and wild mammals only 4%. Approximately 70% of all birds are poultry, so only 30% are wild. To minimize human impact on biodiversity and climate, we have to understand which of our activities are problematic and balance the needs of human civilization and progress with a sustainable plan for future generations. Some of the major threats to biodiversity include habitat loss due to human development, over-farming, and increased carbon dioxide emissions from factories and vehicles. A case study in human impact on the weather can be found in the 1930s event known as the Dust Bowl. In the 1920s and 30s, a large number of farmers moved to the Great Plains and clear cut the land, removing the native ground covering plants in order to

 Core: Biology

Plant Diversity - Student Protocol

JoVE 10636

Viewing Prepared Slides
To start the exercise, first split up into groups and find a station with a compound microscope, dissecting microscope and one prepared slide.
HYPOTHESES: The alternative hypothesis for this experiment might be that plants have specific adaptations that allow them to survive and reproduce in their own individual terrestrial …

 Lab Bio

Natural Selection- Concept

JoVE 10632

Fitness

Widespread variation of phenotypes in natural populations provides the raw material for evolution, which is the change in the inherited traits of populations over successive generations. Natural selection is one of the main mechanisms of evolution and requires variable traits to be heritable and associated with differential survival and/or reproductive success. Phenotypes that…

 Lab Bio
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