Final answer:
The correct answer to the student's question is 'e. cow serum'. Fetal calf serum, widely known as cow serum, is commonly used in mammalian cell cultures as it provides a complex mixture of nutrients, hormones, and growth factors vital for cell growth. Sterile conditions and a solid support are also essential components for successful cell culture.
Step-by-step explanation:
Culture Media Requirements for Mammalian Cell Growth
In the practice of mammalian cell culture, cells must be provided with a supportive environment that mimics their conditions in vivo. The culture medium plays a crucial role as it contains not only nutrients but also supports the growth of the cells by providing necessary components such as hormones, growth factors, and binding proteins. When mammalian cells are placed in culture they typically require a medium enriched with a serum, most commonly fetal calf serum, which contains a vast array of components essential for cell survival and proliferation.
The question asked refers specifically to the requirement of a 10% addition of a particular substance to the culture media to promote cell growth. The correct answer is e. cow serum, which is another name for fetal calf serum, and is extensively used because of its rich composition that provides necessary nutrients, hormones, and other growth-promoting factors. While artificial culture media are also available, they are designed to replicate the complex mixture of biomolecules found in serum.
It is essential to maintain sterile conditions using a laminar flow hood and to provide a solid support for the cells to attach. Successful cell culture leads to what is known as primary cell culture, and subsequent subculturing can take place to expand the number of cells. Over time, repeated cell divisions in vitro may cease due to senescence or inadequate culture conditions.