I believe that in developed nations, the nutrients that are most lacking in a child's diet are the; calcium, iron and zinc. Zinc is needed for the activity of more than 100 different enzymes in the body and plays a role in the immune function. It aids in the maintenance of healthy immune function in kids and may reduce the frequency of mild upper respiratory tract infections. Calcium keeps the bones healthy and teeth thus supporting the skeletal structure and function. Iron is an important component of hemoglobin.
Answer:
B) Nitrogen-fixing bacteria and lightning
Explanation:
Nitrogen cycle is the natural process in which atmospheric nitrogen is converted into nitrite and nitrate with the help of bacteria.
Nitrogen cycle is directly dependent on nitrogen-fixing bacteria and lightning.
As bacteria are responsible for most of the chemical conversion in the nitrogen cycle such as nitrogen fixation (first step) is done by soil bacteria (Cyanobacteria) that form ammonia, which is toxic to plants; nitrification in which ammonia is converted into nitrites and nitrates with the help of Nitrobacter and denitrification bacteria involve Pseudomonas, and Achromobacter which convert nitrite and nitrate into nitrogen.
The lightning breaks nitrogen molecules and allow it to combine with oxygen in atmosphere which further dissolve in rain and form nitrates.
Hence, the nitrogen cycle is most directly dependent upon nitrogen-fixing bacteria and lightning and the correct option is B.
Cell membrane is the answr
Answer:
Abierto es sin vasos y cerrado es con vasos.
Explicación:
El sistema circulatorio abierto es un tipo de sistema que se encuentra en los invertebrados. en el que la sangre fluye libremente a través de las cavidades en lugar de los vasos sanguíneos mientras que, por otro lado, el sistema circulatorio cerrado es un tipo de sistema en el que el corazón bombea sangre y la sangre fluye a través de los vasos y capilares. Este tipo de sistema circulatorio está presente en humanos y vertebrados.
Answer: Antimicrobial proteins.
Explanation:
Antimicrobial proteins are the type of proteins produced by the keratinocytes on the body surfaces. These proteins acts as the barrier and kills the microorganism which is trying to enter the body.
These are larger proteins containing more than 100 amino acids. They are often lytic in nature.
The cell membrane of the microbes is disrupted by the action of these amino acids or proteins on them.