Scientists have concluded that the average human body contains approx. 37.2 trillion cells. However it depends upon your size compared an average human being. :)<span />
Question 1:
<u>Answer</u>:
The "first line of defence" in innate immunity is "Physical and chemical barriers".
<u>Explanation</u>
"Physical and chemical barriers" is first line of defence includes that are ready to defend the living organism's body from infection at any time . These barriers include your skin, cilia, tears, urine flow, mucus, stomach acid, friendly bacteria and white blood cells . Skin acts as a mechanical barrier as it does not allows all the organism to pass through it unless the skin is cut or open. Similarly mouth eyes, and nose are also the ways through with the disease causing organism can enter the body. The micro-organisms that entered through these pathways are trapped either in saliva or mucus and swallowed and later either killed in the stomach or flushed out via the urine. If this first line of defence is broken or damaged, the second line of defence inside our body will be activated.
Question 2:
<u>Answer:</u>
Histamine kinins, and interleukins are examples of inflammatory mediators.
<u>Explanation</u>:
Inflammatory mediators are identified in inflammatory bowel disease IBD.These mediators play an vital role in the clinical and pathologic characteristics of the disorders. Cytokines, that are released by macrophages in due to antigenic stimuli, are binded different receptors and produce endocrine, autocrine and paracrine effects. Interleukins are a subset of a large group of 'cellular messenger molecules' called cytokines that modulates the cellular behaviour. Interleukins are not stored within cells like cytokines but they are released immediately, in response to a stimulus. Once an interleukin has been secreted, it moves to the target cell and binds to it through a receptor molecule on the surface of the cell . This interaction triggers a sequence of signals in the target cell that ultimately leads to the alteration in the behaviour of the cell.
Answer: Tightly wound chromosomes, composed of DNA, must unwind before replication. Cell replication splits a cell into two parts, both of which become new, fully functioning cells. Before this can happen, however, cells require a full complement of DNA for each of the new daughter cells that will form as a result of the split. Because of this, DNA makes a copy of itself in a process known as replication during interphase, a stage that occurs before cells divide.
Cell Phases: Mitosis is the process by which parent cells each divide into two identical daughter cells. However, this majority of the cell's time is spent in interphase, during which it performs normal metabolic functions necessary for the organism, such as manufacturing protein. DNA occurs during the S phase of interphase, sandwiched between the G1 and G2 phases. The cell uses checkpoint signals to ensure at the end of G1 that it is big enough to replicate and at the end of G2 to determine whether or not DNA replication has succeeded. If so, the cell can undergo mitosis, at which point DNA winds up tightly for easy transport during the process.
DNA Replication: Replication begins with DNA unwinding and unzipping, its two strands coming apart. While only one side is the “correct” code, containing the actual genetic information used to build the organism’s proteins, both can be the base for a new strand of complete DNA. The enzyme DNA polymerase matches up each base with the correlating base: adenine with thymine and guanine with cytosine. When each pre-existing base has been matched to a nucleotide, which also contains the sugar and phosphate of the DNA’s backbone, the strand is complete.
Clean or green energy helps in releasing lesser air pollution and lesser carbon dioxide. That contributes in lowing down global warming and subsequent disasters like tsunami because of glacier melting , more unexpected climate changes like unexpected long-period storms, flood, typhoons, etc.
Hope this would help.