All organisms are made up of cells, have different levels of organization, use energy, respond to and adapt to their environments, grow and reproduce. If something does not exhibit each of these characteristics, it is technically not living.
The cell is the basic unit of life, and each living thing consists of one or more cells. An organism shows levels of organization within itself, whether molecular or cellular.
Organisms all need some form of energy to carry on the basic function of life. They also use energy to grow and develop. Once mature, an organism can engage in reproduction to pass its genes on to the next generation. Living things respond to their environments through actions such as moving away from danger.Learn More
Chromosomes exchange genetic information in the form of genes during the process of meiosis. This process creates both egg and sperm cells in females and males, respectively. During meiosis, crossing over occurs between the chromosomes to exchange genetic information and create unique eggs and sperm.Full Answer >
Ribosomes are a type of organelle found in every cell, and their main function is to synthesize proteins for use throughout the cell. In the ribosomes, individual amino acids are arranged into long protein chains according to the sequence of mRNA, or messenger RNA. It is the ribosome's job to read the sequence of mRNA and translate it into the correct sequence of amino acids for each protein that must be made.Full Answer >
DNA copies itself through the process of DNA replication. This process occurs before a cell can divide, so that the new cell obtains a fully functional strand of DNA. In eukaryotes, DNA replication occurs during the S phase of the cell cycle.Full Answer >
Alternative RNA splicing occurs in eukaryotic cells, enabling eukaryotes to make multiple proteins from a single gene. Eukaryotic messenger RNA contains expressed regions called exons and intervening regions called introns. Before mature mRNA exits the nucleus, molecules of small nuclear RNA remove introns and select which exons get joined together.Full Answer >