Question

Bio 254 - Pre-Class Assignment 1

Answer 1

Question 1:

Answer:

The "first line of defence" in innate immunity is "Physical and chemical barriers".

Explanation

"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:

Answer:

Histamine kinins, and interleukins are examples of inflammatory mediators.

Explanation:

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.