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
Answer:
option B) intracellular receptors are present only in target cells.
Explanation:
The cell membrane or plasma membrane is composed of phospholipids and thus hydrophobic in nature, this allows the lipid soluble signaling molecules to cross the membrane. The cell membrane of all cells consist of phospholipids thus hydrophobicity of each cell membrane allows lipid soluble signaling molecules to pass through the plasma membrane. The testosterone cross the membranes of all cells but affect only target cells because of intracellular recepters that are located in target cell. The binding of signaling molecules to recepter generates a response. Thus, option B is correct.
Answer:
Core is the densest layer of the earth.
Explanation:
The structure of the earth's interior is made up of several concentric layers. The earth's interior is divided into three layers- The Crust, the mantle and the core. The density of the outermost layer the crust is 3 g/cm^3. As we move towards the interior, the earth become more dense. The density of the second layer mantle ranges between 2.9-3.3 g/cm^3. The core is the innermost layer of the earth, surrounding the earth's center. the density of the core ranges between 9.5-14.5 g/cm^3.
Answer:
C- it helps develop scientific consensus by making sure new ideas are critically evaluated.
The acids have more H+ while bases have more OH-. About pH, typically under room temperature, when a solution has pH<7, it is acid. When pH>7, it is base. And when pH=7, it is neutral.
