BioSafety Level (BSL) 3 labs,
perform work with indigenous or exotic agents that may cause serious or
potentially lethal diseases through the inhalation exposure. Biological Safety
Levels (BSL) are a sets of protections assigned to the activities that occur in
specific biological laboratories. BSL protects laboratory workers, the
surrounding environment and also the community.
Answer: It's known as the continental drift :)
Explanation: "Pangea's existence was first proposed in 1912 by German meteorologist Alfred Wegener as a part of his theory of continental drift. Its name is derived from the Greek pangaia, meaning “all the Earth.”" (copied from google)
Prokaryotes are unicellular (single-celled) organisms and on the other hand Eukaryotes are multicellular organisms and more developed in organ and structure compared to prokaryotes. Gene regulation is key to both organisms as it determines growth and development and other process and activities performed by the organism. However, the two organisms differ in the way they regulate their genes. Prokaryotes cells lack nucleus while the eukaryotic cells have a well defined nucleus. In Prokaryotes RNA transcription and protein formation occur almost simultaneously while in the Eukaryotes RNA transcription occur before the protein formation in the nucleus and then protein formation occurs in the cytoplasm. In addition both organisms uses the same processes in gene regulation and only differ in the manner the processes are undertaken. Lastly, gene expression in prokaryotes is regulated at transcriptional level whereas in eukaryotes regulation is at many levels.
Answer: D. Extinctions occur at higher rates during times of ecological stress when populations and species are poorly adapted.
Answer: Sphincter muscles
Explanation:
The circular rings of smooth muscles, that can contract to regulate the movement of the smooth muscles that can contract to regulate the movement of food through the gastrointestinal tract are known as sphincter muscles.
These two layers are outer layer and inner layer. The outer layer is longitudinal and the inner layer is circular. They contract rhythmically to squeeze food.
