Answer:
True
Explanation:
Elastic fibers are composed of elastin, myofibrils and fibrillin. They are distributed <u>separately</u>, and therefore do not form bundles(they actually form a kind of mesh), like collagen fibers.
Elastic fibers are usually thin and long and can stretch up to 1.5x of their total length.
These fibers confer elasticity to the connective tissue. The mesh formed of elastic fibers easily yields to minimal tensions, returning to its original shape as soon as the deforming forces cease.
An example of the action of elastic fibers is when we pull the skin from our hands and release it, the elastic fibers are responsible for quickly returning the skin to its original shape.
A) <u>Mutation</u> is the original source of variations for plants and other organisms which develops differences among their respective species
Explanation:
Genetic variation leads to the natural differences between each individual and among individuals of a species. The main cause for this variation is due to alleles that cause variations in the composition of genes or the DNA sequences.
A mutation is a genetic variation which leads to the creation of a new allele in a species population. Each variation in the DNA sequence leads to an allele formation and each allele leads to a difference in character or trait between individuals since they are the alternate version of the original genes.
Although genetic variations could be brought about by crossing over, random fertilization, or independent assortment; mutation is the original source because it provides the basic raw material for all the evolutionary changes.
Answer: Nervous system
Explanation:
The cerebellum of the brain is the structure of the nervous system known to control various muscles of the body that are involved in involuntary activities such as breathing.
Thus, the nervous system controls and regulates a person's breathing
Answer:
a) Las raíces superficiales y extensas
c) El cuerpo carnoso de las plantas
d) Las hojas modificadas en forma de espina
Explanation:
En biología, una adaptación refiere al proceso de cambio evolutivo mediante el cual los organismos de una especie/taxón hacen frente a determinadas condiciones ambientales. Las plantas han desarrollado diferentes adaptaciones en ambientes desérticos a fin de evitar al máximo la pérdida de agua, el factor más limitante en este tipo de ambientes. Las plantas capaces de soportar largos periodos de sequías se denominan xerófitas. En primer lugar, además de servir como una buena defensa contra herbívoros, las hojas en forma de espina le permiten a una planta almacenar agua durante los períodos de precipitaciones. En segundo lugar, las raíces de plantas desérticas pueden disponerse superficialmente con el objetivo de absorber la mayor cantidad de agua posible. En tercer lugar, las plantas suculentas o crasas son aquellas que tienen tejidos carnosos los cuales pueden almacenar agua en sus hojas, tallos o raíces. Durante los periodos de lluvia leve, las suculentas almacenan grandes cantidades de agua para sobrevivir durante la temporada seca (incluso existen especies vegetales que sobreviven solamente durante la temporada húmeda y producen semillas que toleran la temporada seca).
<span>A unique feature of dna is that it can duplicate itself through a process called replication.</span>
