The public health measures that are most effective against pathogens transmitted through common vehicles are the water purification and food safety regulations. The most common vehicles or modes of transmission of infectious pathogens includes water, food, air, or the blood during transfusion. Ensuring use and supply of clean water and also safety food regulations may reduce the spread and transmission of disease causing pathogens.
Answer:
Blood is not present in the urine of healthy person since the blood cells, platlets and plasma proteins are large enough to prevent their glomerular filtration. These components of blood are not present in the glomerular filtrate and hence, are absent in urine as well.
Explanation:
The first step in urine formation is glomerular filtration which filters the nitrogenous wastes and other compounds and forms glomerular filtrate. Glomerular filtrate undergoes tubular reabsorption and tubular secretion to form urine.
The components of blood such as blood cells, platelets, proteins of plasma are not added to the glomerular filtrate. They exit the glomerulus of nephrons via efferent arteriole. Since blood components are not filtered to become part of glomerular filtrate, blood is absent in the urine of a healthy person.
When a microbe that is not part of the normal biota enters the body, it is likely to first encounter first line of host defense.
The term "normal microbiota" describes the microorganisms that are present in every human's conjunctiva, oral mucosa, skin's surface and deeper layers, saliva, and gastrointestinal tracts. The host employs a number of defences to defend against infection.
Mucus, which has a variety of normal microbiota that compete with and may even destroy invasive bacteria and virae, is one of the body's first lines of defence.Once a virus or bacteria penetrates the skin and mucosa, the host may experience changes that lessen the invader's power. A fever is one instance of such a shift.
Therefore, When a microbe that is not part of the normal biota enters the body, it is likely to first encounter first line of host defense.
Learn more about first line of host defense here:
brainly.com/question/20523292
#SPJ4
Answer: Venus, Mercury and Mars are the differentiated planets.
Planetary differentiation can be defined as the process by which the separation of different types of constituents takes place. They are differentiated on the basis of their chemical or physical behavior.The denser material of the planets sink to the center of the planet and the less denser particles rise at the surface of the planet.
A, b, and c are all correct.
take for example finches off of the galapagos islands. they vary from island to island, yet are still the same bird. on one island they have bigger, more durable and stronger beaks, because that island has many nuts to crack open and eat. on another island, they have thin ling beaks, ideal for pecking at insects in the grass on tree bark. evolution is literally survival of the ifttest, where those equipped best will live and those without means to fight for life will die off, leaving those most capable of reproduction and passing down genes.
