Related Concept Videos

Directional Terms01:14

Directional Terms

Directional terms are essential for describing the relative locations of different body structures. For instance, an anatomist might describe one band of tissue as "inferior to" another, or a physician might describe a tumor as "superficial to" a deeper body structure. These terms often use comparative terms in pairs to trace out the relative locations of one body part to another or descriptions of body tissues like the deeper ones from superficially present with reference to the body's upright...
Spare Receptors01:30

Spare Receptors

Some receptors remain unoccupied even when an agonist produces a maximal response. Such empty ones are called spare receptors. In presence of spare receptors the maximum effect of an agonist drug is achieved with fewer than 100% of the receptors being occupied. To determine the presence of spare receptors, scientists often compare the concentration of the drug needed to produce 50% of the maximum effect (EC50) with the concentration of the drug needed to occupy 50% of the receptors (Kd). If the...
Adhesion01:14

Adhesion

Adhesion occurs when one type of molecule is attracted to a different molecule. Water exhibits adhesive properties in the presence of polar surfaces, such as glass or cellulose in plants. For instance, when water is poured into a glass, the positively charged hydrogen molecules of water are more attracted to the negatively charged oxygen molecules in the silica than to the oxygen in neighboring water molecules.
Capillary action is a result of water’s adhesive tendencies. When a narrow glass...
Genetic Lingo01:11

Genetic Lingo

Overview
Competition02:34

Competition

When organisms require the same limited resources within an environment, they may have to compete for them. Competition is a net-negative interaction. Even if two competing individuals or populations do not interact directly, the overall fitness of both competitors is lowered as a result of not having full access to the limited resource.Intraspecific competition, which occurs between individuals of the same species, serves as a natural mechanism for regulating population size. Too much...
Wood Fasteners01:18

Wood Fasteners

In wood construction, fasteners are essential for securing components together, with the connection strength largely dependent on the direct bearing between members. Various types of fasteners are employed, each suited to specific applications and structural requirements.
Nails are the most common fasteners, consisting of sharp-pointed metal pins that are driven into wood using a hammer or a mechanical nail gun. They come in a variety of diameters, heads, and lengths. Nailing techniques include...