Answer:
A chromosome is a DNA (deoxyribonucleic acid) molecule with part or all of the genetic material (genome) of an organism. Most eukaryotic chromosomes include packaging proteins which, aided by chaperone proteins, bind to and condense the DNA molecule to prevent it from becoming an unmanageable tangle. This three-dimensional genome structure plays a significant role in transcriptional regulation.Chromosomes are normally visible under a light microscope only when the cell is undergoing the metaphase of cell division (where all chromosomes are aligned in the center of the cell in their condensed form). Before this happens, every chromosome is copied once (S phase), and the copy is joined to the original by a centromere, resulting either in an X-shaped structure (pictured here) if the centromere is located in the middle of the chromosome or a two-arm structure if the centromere is located near one of the ends. The original chromosome and the copy are now called sister chromatids. During metaphase the X-shape structure is called a metaphase chromosome. In this highly condensed form chromosomes are easiest to distinguish and study.In animal cells, chromosomes reach their highest compaction level in anaphase during chromosome segregation.
Chromosomal recombination during meiosis and subsequent sexual reproduction play a significant role in genetic diversity. If these structures are manipulated incorrectly, through processes known as chromosomal instability and translocation, the cell may undergo mitotic catastrophe. Usually, this will make the cell initiate apoptosis leading to its own death, but sometimes mutations in the cell hamper this process and thus cause progression of cancer
Rosalind Franklin found out that the structure of DNA is shaped like an X when looked at through a microscope meaning that the shape of DNA is a double helix. Other scientists later used this information to discover other important things about DNA
YES THAT FIRST SENTENCE IS VERY TRUE.YES, GENE DOPING IS USED BY MANY ATHLETES AROUND THE WORLD.IT CAUSES SEVERAL EFFECTS LIKE:
a) increased extraordinary hematocrit
b) increased thrombotic activity
c) autoimmune anemia,ETC.
ANY TWO GENETIC MODIFICATIONS THAT WOULD IMPROVE THE PERFORMANCE OF AN ATHLETE ARE:
a.gene therapy should be given to produce more hormones in the body.
b. gene therapy is given to athletes because they have been used to study and model cancer (the oncomouse), obesity, heart disease, diabetes, arthritis, substance abuse, anxiety, aging and Parkinson disease to check for the athletes.
Answer and explanation;
Contraction of skeletal muscles;
-An action potential from a motor neuron triggers the release of Ca2+ ions from the sarcoplasmic reticulum.
-Calcium ions expose the myosin heads by binding to a blocking molecule (troponin complexed with tropomyosin) and causing it to move.
-The myosin heads form a cross-bridge with actin binding sites.
-ATP binds to the myosin heads and breaks the cross-bridge.
-The hydrolysis of ATP causes the myosin heads to change shape and swivel - this moves them towards the next actin binding site.
-The movement of the myosin heads cause the actin filaments to slide over the myosin filaments, shortening the length of the sarcomere.
-Via the repeated hydrolysis of ATP, the skeletal muscle will contract.
