Answer:
Transition metals
Explanation:
The transition metals are usually harder than other metals such as the alkali metal, lanthanide series metals and the alkaline earthmetals.
The reason for this is because they have a stronger metallic bonding between their atom.
Hardness is a physical property which is attributed to intermolecular forces and the atomic arrangement
The transition metals are found in the d - block on the periodic table.
They have a d-orbirtal which confers extra electrons and higher degree of stability to the atom. The d-orbirtal provides more delocalized electrons for the metallic bonds formed.
Answer:
c. Left atrium
j. right atrium
f. left ventricle
g. right ventricle
Explanation:
The heart consists of four chambers that is two ventricles and two articles.
Blood enters the right atrium goes into the right ventricle.
The right ventricle then pumps blood into the lungs where the blood gets oxygenated.
Pulmonary vein then brings back the blood from lungs into the left ventricle, blood is pumped into the left atrium and out of the heart.
That is the process through which blood navigates in the heart.
Answer:
Una de las características de los seres vivos se encuentra en su composición biológica, dado que todos ellos están constituidos por cuatro bioelementos esenciales que se encuentran de manera abundante en la naturaleza:
Carbono
Hidrógeno
Oxígeno
Nitrógeno
Estos bioelementos o elementos biogénicos están presentes en las biomoléculas, que son las que dan forma a la materia que constituye a los seres vivos. Estas moléculas están formadas, a su vez, por la unión de átomos.
De estos bioelementos, es importante destacar el papel del hidrógeno y el oxígeno, que dan lugar a la molécula del agua. El agua, o H2O, juega un papel fundamental en el funcionamiento de los seres vivos.
Answer:
Oxygen and pyruvate.
Explanation:
The krebs cycle is a stage of cellular respiration and occurs in aerobic organisms. In this case, we can say that the Krebs Cycle only occurs in the presence of oxygen, being essential for the completion of cell respiration.
The Krebs cycle only occurs after the completion of glycolysis, as it needs to be initiated by pyruvate, which is a molecule resulting from glycolysis. In this case, in addition to oxygen, the presence of pyruvate is essential for the krebs cycle to occur.