Answer:
The correct answer is 0.26 M
Explanation:
The initial concentration of NaCl solution (Ci) is 5.0 M. The initial volume of the solution (Vi) is 13 mL. The final volume is the addition of 240 mL to 13 mL (Vf= 13 mL + 240 mL= 253 mL).
In order to calculate the final concentration of the solution (Cf) we can use the following expression:
Ci x Vi= Cf x Vf
This mathematical expression is often used to calculate concentrations in dilution procedures. So, we introduce Ci, Vi an Vf in the expression and we calculate Cf:
Cf= (Ci x Vi)/Vf= (5.0 M x 13 mL)/253 mL= 0.257 M ≅ 0.26 M
The nitrogen containing amino group is recycled while the remainder of the molecule is excreted in the urine
Answer:
sun
Explanation:
there would be no life whatsoever if we have the sun.
Answer:
The answer is <em><u>D.
</u></em>
Explanation:
Viruses can evade the processing and presentation of antigens, for example by interfering with the expression of MHC class I proteins, although this increases their susceptibility to be detected by natural killer cells (NK). However, some members of the herpesvirus, papillomavirus, retrovirus, poxvirus and flavivirus families have also developed strategies to escape the attack of NK cells and promote their survival, inhibiting cell apoptosis. Finally, some pathogens often change surface antigens frequently, as in the case of influenza viruses (orthomyxovirus).
The human immunodeficiency virus (HIV) affects CD4 + T cells and degrades the host's ability to counterattack with a strong cell-mediated immune response. There are so many tactics of immune evasion used by HIV, which have so far hindered the development of an effective vaccine.
