Yes, the cell membrane regulates what enters the cell and leaves the cell. The cell membrane is a fluid mosaic consisting of a phospholipid bilayer and integral and peripheral proteins. The proteins of the membrane serve many purposes: transport, receptors, etc. The cell membrane is amphipathic, meaning is has hydrophilic and hydrophobic regions.
as the question is incomplete i have attached the full question with solution. see attachment. This question is matching pair therefore i compiled it in a picture format for better understanding.
Answer:
Yes, two hydrogen bonds could form between thymine and cytosine.
Explanation:
Cytosine is a pyrimidine base found in both DNA and RNA, and Thymine is a pyrimidine base found in only DNA. Electronegative Oxygen and Nitrogen atoms with free lone pairs are potential hydrogen bond acceptors. Hydrogen atoms attached to very electronegative atoms like Oxygen and Nitrogen have strong partial positive charge and are potential hydrogen bond donors.
One hydrogen bond could form between the C4 carbonyl group on thymine which is a hydrogen bond acceptor and the C4 amino group on cytosine which is a hydrogen bond donor. Also, another hydrogen bond could be formed between N3 of thymine which is a hydrogen bond donor and the N3 of cytosine that is a hydrogen bond acceptor.
It is important to note that hydrogen bond cannot be formed between them because the C2 carbonyl groups found on both bases are both hydrogen bond acceptors.
Answer:
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Explanation:
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Answer:
The correct answer is option d. "Polyclonal antibodies".
Explanation:
The enzyme-linked immunosorbent assay (ELISA) is very useful in comparison to other immunoassay methods for being highly accurate, sensitive and specific. Polyclonal antibodies for the detection step could be used on order to ensure that a mutation in a single surface protein would not make obsolete an ELISA used to detect a new viral pathogen. Unlike monoclonal antibodies, polyclonal antibodies are a collection of antibodies that recognize multiple epitopes of the same antigen. Therefore, a mutation in one epitope that affects the binding of one antibody would not affect the bind of the others and the ELISA will be able to recognize the pathogen.
