A vital aspect of a forensic investigation may be to detect and …
A vital aspect of a forensic investigation may be to detect and locate specific people or substances of interest, ranging from illegal drugs to missing people to clandestine graves. Sophisticated detection equipment does exist, however this technology can often be expensive, have unsuitable portability, and may even prove useless when searching vast areas. Fortunately for investigators, there is an ideal tool available. Dogs, sometimes known as K9s or sniffer dogs by law enforcement professionals, have played an important role in legal investigations for decades, with their keen sense of smell being harnessed to aid investigations. The average human being has roughly five million sensitive cells within the nose to aid in scent detection. This appears to be a large number, until compared with the 200 million cells in the average dog’s nose. Further increasing the canine’s sense of smell is an organ in the roof of the mouth that is not present in humans. This organ essentially allows the dog to ‘taste’ a smell, thus strengthening its ability to detect odours. Canines detect odours directly from the source or residual scents; odours which persist in an area after the original source is no longer present. Obviously the air is full of a vast variety of different odours, many of which will be powerfully clear to the dog. Fortunately they are able to distinguish between different odours, even if one smell overpowers another, and trace a specific scent to its source.
Students use two different methods to determine the densities of a variety …
Students use two different methods to determine the densities of a variety of materials and objects. The first method involves direct measurement of the volumes of objects that have simple geometric shapes. The second is the water displacement method, used to determine the volumes of irregularly shaped objects. After the densities are determined, students create x-y scatter graphs of mass versus volume, which reveal that objects with densities less than water (floaters) lie above the graph's diagonal (representing the density of water), and those with densities greater than water (sinkers) lie below the diagonal.
This short video and interactive assessment activity is designed to teach third …
This short video and interactive assessment activity is designed to teach third graders about determining unknown angles within rectangles and squares.
In this problem-based learning (PBL) activity, students take on the role of …
In this problem-based learning (PBL) activity, students take on the role of a student research scientist and explore the role of solar energy in determining climate, focusing on the urban heat island effect. Students conduct research and compare temperatures between two cities, and determine the factors that are responsible for the difference exhibited between them. The lesson is supported by teacher notes, answer key, glossary and an appendix with information about using PBL in the classroom. This is the third of three activities in Investigating the Climate System: Energy, a Balancing Act, and serves as an authentic assessment for all three modules.
In this deterministic cellular automata model, interactions between neighboring automata are described …
In this deterministic cellular automata model, interactions between neighboring automata are described using a prisoner's dilemma. Limiting dispersal of seeds of annual plants can permit heterogeneous co-existence, whereas thorough mixing instead allows one subpopulation to dominate quickly.
This self directed PD consists of the following learning modules: Developing ACL …
This self directed PD consists of the following learning modules:
Developing ACL Pre-Assessment Overview: What is an Assessment Capable Learner? Part 1: Where Am I Going? Part 2: Where Am I Now? Part 3: How Can I Close the Gap? Developing ACL Post-Assessment Closing and Follow-Up: Developing ACL
No restrictions on your remixing, redistributing, or making derivative works. Give credit to the author, as required.
Your remixing, redistributing, or making derivatives works comes with some restrictions, including how it is shared.
Your redistributing comes with some restrictions. Do not remix or make derivative works.
Most restrictive license type. Prohibits most uses, sharing, and any changes.
Copyrighted materials, available under Fair Use and the TEACH Act for US-based educators, or other custom arrangements. Go to the resource provider to see their individual restrictions.
