Answer:
Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations.
Explanation:
Answer:
el niño tendría síndrome de downEl síndrome de Down es causado por un error aleatorio en la división de las células que tiene como resultado la presencia de una copia extra del cromosoma 21.
Answer:
Sodium-Potassium pumps (proteins that help neurons generate electricity) are produced by ribosomes on the rough endoplasmic reticulum (ER).
Explanation:
Sodium-Potassium Pump (NA+/K+):
The Na+/K+ Pump is a transmembrane channel protein, responsible for maintaining the concentration gradient of sodium and potassium ions in the intra and extracellular environment. This is achieve by pumping 3 Na+ outside and 2 K+ inside the cell at the cost of one ATP. In neurons, these channels help in generating an action potential across the cell membrane that gives rise to a nerve impulse.
Production of Transmembrane proteins:
All membranes and their proteins are produced by the ribosomes on the rough ER. The rough endoplasmic reticulum contains the enzymes required for lipid synthesis; and as cell membranes are made of lipids, the ER is the most suitable location for synthesis. Membrane proteins, particularly, transmembrane proteins like the Na+/K+ pump possess hydrophobic surfaces that don't dissolve in the cytoplasm but readily attach to the ER surface from where they can be transported wherever required.
Answer:
Hydrogen Bonds
Explanation:
In the polymerase chain reaction (PCR) the temperature rises to 90 ° C - 95 ° C, to break the hydrogen bonds, which are the types of bonds responsible for pairing the two strands of DNA, this process is known as denaturation of DNA.
The DNA is extremely stable, due to a large number of bonds (hydrogen bonds) that form between the two strands. If the temperature decreases, these bonds will begin to recompose, until the DNA returns to its original state