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,
Answer:
The first genetic code is used to determine the nucleotide triplets that code for amino acids.
Explanation:
The second genetic code is used by the amino acid synthetase in order to determine whether the correct tRNA is being used for it's corresponding amino acid.
Maybe biosphere and geosphere?
The correct answer is (b) arctic fox
The arctic fox shows two color of fur depending upon the season. During summer and spring season the fox has dark colored coat .It does so to match the color of the brown dirt in the surrounding. In winter's the arctic fox turns its fur to white to match the color of the snow in the surrounding. This phenomenon is known as " camouflage". Animals have developed this adaptation to protect itself from being killed by other animals by changing the color of the fur according to the color of the surrounding.
