Which of the following organisms is not nekton? a. Whales
b. Crabs (answer)
c. Sharks
d. Dolphins
The cell membrane is semi permeable in nature, that is, it allows the passage of some substances while it disallows some substances. Small and non polar molecules pass quite easily through the cell membrane but large and polar molecules can not do this.
The substances which can easily pass through the cell membranes make use of passive transports such as diffusion and facilitated diffusion to enter the cells while substances which can not pass through the cell membranes on their own make use of active transport. Examples of active transport are endocytosis and ectocytosis,
Last option: Preserve an ecosystem
• The establishment of a bird reservation is a way to preserve an ecosystem because reservation provides suitable environment to organism. A healthy ecosystem means large number of biodiversity.
Faunal Succession—The principle of faunal succession, also known as the law of faunal succession, is based on the observation that sedimentary rock strata contain fossilized flora and fauna, and that these fossils succeed each other vertically in a specific, reliable order that can be identified over wide horizontal distances.
Original Horizontality—The Principle of Original Horizontality states that layers of sediment are originally deposited horizontally under the action of gravity. It is a relative dating technique. The principle is important to the analysis of folded and tilted strata.
lateral continuity—The principle of lateral continuity states that layers of sediment initially extend laterally in all directions; in other words, they are laterally continuous. As a result, rocks that are otherwise similar, but are now separated by a valley or other erosional feature, can be assumed to be originally continuous.
Superposition—Superposition is the ability of a quantum system to be in multiple states at the same time until it is measured.