Related Concept Videos

The Evidence for Evolution02:55

The Evidence for Evolution

Genetic variations accumulating within populations over generations give rise to biological evolution. Evolutionary changes can result in the formation of novel varieties and entire new species. These changes are responsible for the diverse forms of life inhabiting the planet. The evidence for evolution suggests that all living organisms descended from common ancestors.
48.3K
Frustration and Conflict: Approach-Approach, Approach-Avoidance01:20

Frustration and Conflict: Approach-Approach, Approach-Avoidance

Frustration occurs when people are obstructed or prevented from achieving a desired goal or fulfilling a perceived need. For example, when someone's input is ignored in a discussion, it can lead to feelings of frustration. Conflict, however, arises from opposing interests, goals, or actions. Conflicts can take various forms based on the nature of these opposing desires or goals.
One common type of conflict is the Approach–Approach Conflict. In this case, a person faces two desirable...
537
Frustration and Conflict: Avoidance-Avoidance, Double-Approach Avoidance01:14

Frustration and Conflict: Avoidance-Avoidance, Double-Approach Avoidance

Avoidance-avoidance conflict refers to a psychological situation where a person must choose between two or more unpleasant alternatives. These conflicts are particularly stressful because neither option is desirable. This dilemma is often expressed in sayings like "caught between a rock and a hard place" or "between the devil and the deep blue sea." For instance, individuals who fear dental procedures may find themselves torn between enduring a painful toothache or facing the...
686
What are Cells?01:07

What are Cells?

Cells are the smallest and basic units of life, whether it is a single cell that forms the entire organism, e.g., in a bacterium or trillions of them, e.g., in humans. No matter what organism a cell is a part of, they share specific characteristics.
Basic Characteristics of Cells
A living cell has a plasma membrane, a bilayer of lipids that separates the aqueous solution inside the cell called the cytoplasm from the outside environment.
Furthermore, a living cell possesses genetic information...
200.7K
What is Cell Signaling?02:03

What is Cell Signaling?

Despite the protective membrane that separates a cell from the environment, cells need the ability to detect and respond to environmental changes. Additionally, cells often need to communicate with one another. Unicellular and multicellular organisms use a variety of cell signaling mechanisms to communicate to respond to the environment.
130.9K
Chemistry of the Cell02:58

Chemistry of the Cell

The cell is chemically composed of water, organic molecules and inorganic ions.
Water
The polarity of the water molecule and its resulting hydrogen bonding makes water a unique substance with special properties that are intimately tied to the processes of life. Life originally evolved in an aqueous environment, and most of an organism’s cellular chemistry and metabolism occur inside the aqueous contents of the cell’s cytoplasm. Special properties of water are its high heat capacity...
48.0K