Answer:
Crossing over and random alignment are the events of meiosis-I that add new gene combinations to the gametes. Random fusion of male and female gametes is called random fertilization.
Explanation:
During the pachytene stage of meiosis-I, part of the chromatids of each of the homologous chromosomes of a bivalent is broken apart and exchanged. This exchange of the genetic material between the members of a bivalent is called crossing over. The recombinant chromatids formed by crossing over have new allele combinations that were otherwise not present in the parental chromatids.
During metaphase I, the homologous pairs are aligned at the cell's equator in a random manner. This means that either the paternal or maternal chromosome of a pair may face one or the other pole of the cell. The arrangement of chromosomes during metaphase-I determines whether the paternal or maternal chromosome of each pair would be distributed to one or the other pole of the cell. This random segregation creates new gene combinations in gametes.
All the gametes have equal chances of getting fused with a gamete from the opposite gender. This is called random fertilization and further adds variations.
Answer:
1. Nutrientes:
- alimento
- oxígeno (O2)
2. Productos de la nutrición animal:
- residuos orgánicos
- dióxido de carbono (CO2)
Explanation:
Los alimentos son sustancias químicas que los animales ingieren a fin de que el organismo transforme dichos compuestos en nutrientes los cuales son requieridos para la generación, el crecimiento y la reconstrucción de células y tejidos.
El oxígeno (O2) es un nutriente escencial para la vida el cual se absorbe mediante el proceso de respiración. Este proceso posibilita la absorción de otros nutrientes obtenidos a través de la alimentación.
Los residuos orgánicos representan productos de la nutrición animal los cuales se descomponen naturalmente para formar parte de la materia orgánica. En animales, los desechos órganicos son eliminados a través de los excrementos o en la orina.
El dióxido de Carbono (CO2) es un producto de la respiración. En animales, la respiración celular consume oxígeno y compuestos orgánicos con el objetivo de producir energía en forma de ATP. Como concecuencia del proceso de respiración, los animales liberan CO2 al medio ambiente.
Answer:
1.- Arachnoid mater: Middle meninx; web-like.
2.- Dura mater<u>:</u> Tough, outer meninx.
3.- Epidural space: Space filled with adipose tissue.
4.- Pia mater: Thin meninx intimate with spinal cord.
5.- Subarachnoid mater<u>:</u> Contains cerebrospinal fluid.
6.- Denticulate ligaments
: Extension of pia mater attaching to dura.
<span>The correct answer is B. Insertion. In this particular insertion there is an insert of three bases. Complementary strands in DNA are the opposite strand, so Adenine is coupled to Thymine and Guanine is coupled to Cytosine. So the complementary sequence (also called the antisense strand) of the original would be GTC GGC ATC, there's an extra 3 bases in there: ACA.</span>
Answer:
the cell cycle
Explanation:
Image of the cell cycle. Interphase is composed of G1 phase (cell growth), followed by S phase (DNA synthesis), followed by G2 phase (cell growth). At the end of interphase comes the mitotic phase, which is made up of mitosis and cytokinesis and leads to the formation of two daughter cells.