The correct answer is sarcomere.
A sarcomere refers to the fundamental unit of striated muscle tissue. It is the reiterating unit between the two Z lines. The skeletal muscles comprise tubular muscle cells known as muscle fibers or myocytes that are produced in the procedure called myogenesis.
When the muscle fibers of a motor unit attain an impulse, it instigates a response in each sarcomere between the myosin and actin filaments. This response leads to a start of a contraction and the sliding filament theory.
Answer:
Explanation:
The genes in DNA encode protein molecules, which are the "workhorses" of the cell, carrying out all the functions necessary for life. For example, enzymes, including those that metabolize nutrients and synthesize new cellular constituents, as well as DNA polymerases and other enzymes that make copies of DNA during cell division, are all proteins.
In the simplest sense, expressing a gene means manufacturing its corresponding protein, and this multilayered process has two major steps. In the first step, the information in DNA is transferred to a messenger RNA (mRNA) molecule by way of a process called transcription. During transcription, the DNA of a gene serves as a template for complementary base-pairing, and an enzyme called RNA polymerase II catalyzes the formation of a pre-mRNA molecule, which is then processed to form mature mRNA (Figure 1). The resulting mRNA is a single-stranded copy of the gene, which next must be translated into a protein molecule.
During translation, which is the second major step in gene expression, the mRNA is "read" according to the genetic code, which relates the DNA sequence to the amino acid sequence in proteins (Figure 2). Each group of three bases in mRNA constitutes a codon, and each codon specifies a particular amino acid (hence, it is a triplet code). The mRNA sequence is thus used as a template to assemble—in order—the chain of amino acids that form a protein
But where does translation take place within a cell? What individual substeps are a part of this process? And does translation differ between prokaryotes and eukaryotes? The answers to questions such as these reveal a great deal about the essential similarities between all species.
Answer:
Because different countries have different languages and call the species different things
Explanation:
Answer:
According to Darwin's theory of evolution, new species evolved as a result of natural selection.
Explanation:
- Darwin proposed that speciation could readily occur through the prolonged action of Natural selection.
- Natural selection allows the 'survival of the fittest' i.e. a more fit organism will have a better chance of survival than the less fit one.
- The result of Natural selection could be positive,negative or balancing.
- Evolutionary process in which the genetic changes confer a higher fitness to increase frequency of the organism over time in population is called positive selection.
- Evolutionary process in which genetic changes decreases the organism's fitness resulting in its disappearance from the population is called Negative selection.
- It may happen that a mutation benefits hetero-zygotes but not homo-zygotes and alleles maintain a intermediate frequency in population.This evolutionary process is called balancing selection.
Answer:
Friction: A force that opposes the motion of objects that touch as they move past each other. Friction acts at the surface where objects are in contact.
Explanation:
The force that acts against your pushing force is called friction. is a force that resists the motion between two surfaces in contact. When you try to slide two surfaces across each other, the force of friction resists the sliding motion.