A student makes a model to represent community as a level of organization within a desert ecosystem. Which list of items should the student choose for the model? *

1.six saguaro cacti and a cup of sand
2.three sand dunes and a cup of water
3.three saguaro cacti, five roadrunners, and two rattlesnakes

The correct answer is - 3. three saguaro cacti, five roadrunners, and two rattlesnakes.

Explanation:

A community is a group of interacting populations, in a particular ecosystem, of different species. The group of the same species is known as the population of the ecosystem. In the desert ecosystem, there should be a different group of populations should be found that interact with one other.

Among the given options, the third list has a different kind of species present three saguaro cacti, five roadrunners, and two rattlesnakes interact with one other and depend on one other for food and energy.

white blood cells or wbc s are mainly 2 types-

1.agranulocytes

2.granulocytes

the monocytes or macrophages of agranulocytes , dendritic cells which are accessory leucocytes, and b cells which is one type of lymphocytes   identify the antigens present on the pathogen's surface. these three cells are called antigen presenting cells(apc) which are phagocytes and destroy the antigens by secreting antitoxins. besides this leukocyte is always plays vital role in the immunity of the body.

when the displaced particles are perpendicular to the direction the wave travels, is called a transverse wave, whereas in longitudinal wave the displace practices are parallel to the direction of the wave.

in the given image:

first image shows - longitudinal wave

second image shows - transverse wave

third image shows - longitudinal wave

fourth image shows - longitudinal wave