<span>Compound Microscope
Compound microscope is commonly used in the schools and colleges.
It comes under the category of microscopes used in biology.
It has two lenses namely the objective lens and the ocular lens.
It provides a magnification of 1500X.
Eyepiece lens is of 10X or 15X power.
It is used to observe bacterial, protozoa, various cells, etc.</span>
Answer:
Adenina (30%), citosina (15%), guanina (15%) o timina (40%)
Explicación:
El 30% de las bases nitrogenadas totales lo ocupa la adenina, el 15% de las bases nitrogenadas totales corresponde a la citosina, el 15% de las bases nitrogenadas totales toma la guanina y el 40% restante de las bases nitrogenadas totales lo ocupa la timina. Entonces, al combinar todos estos porcentajes, obtenemos el 100 por ciento del volumen del ácido desoxirribonucleico (ADN).
If a p53 gene is defective it may cause cell cycle to stop functioning normally. Without this cell cycle check, cells will divide continuosly creating many chromosomal damage.
Answer:
TNF-alpha is expressed as a homotrimer that exerts its activities through binding to two types of receptors: TNFR1 and TNFR2, which are transmembrane glycoproteins characterized by having an extracellular domain with 4 cysteine-rich domains (CRD 1-4) , each with 3 cysteinecysteine disulfide bonds.
Explanation:
TNF-alpha (Tumor Necrosis Factor), which has the characteristic of being a paracrine signaling ligand, is a pleiotropic cytokine that functions as a mediator of immune regulation, the inflammatory response and apoptosis in some cell types. Receptors in this family are involved, with some exceptions, in juxtacrine signaling; that is, both the ligand and the receptor are membrane proteins with extracellular domains through which signaling is established. The cellular responses promoted by TNF are initiated by its interaction with two different types of cell receptors, the type I receptor (55 kDa) and the type II receptor (75 kDa). Both types of receptors are part of the TNF receptor family, members of which include Fas antigen (apoptosis inducer, also called Apo-1 or CD95), CD27 (T-cell activation antigen), CD30 (lymphoma marker Hodgkin) and CD40 (B-cell antigen), which share the characteristic of cysteine-rich sequences in their extracellular domains. This family of cytokines generate cellular responses that include differentiation, proliferation, activation of NFκB and cell death, promoting the aggregation of receptor monomers, that is, they have a transmembrane domain that participates in the solubilization of the receptor and a domain of intracellular death that is involved in signal transduction. The binding of TNF to TNF-R1 induces a signaling cascade through its intracellular death domain, which subsequently leads to the activation of complex I (or inflammatory) of NFkB and proceeds to the transcription of anti-apoptotic genes, pro- inflammatory diseases and apoptosis complex II (caspases).
