Answer:
Microtubules have shapes like a spindle and are arranged to form centrosome and a cluster of such microtubules form centriole.
Explanation:
Microtubules are seen in eukaryotic cells to give shape and structure to the cells and they form part of the cytoskeleton. They are known to grow long and are dynamic. Centrosomes are known to be main microtubule that are found in animal cells. They are organelles that are made from the arrangement of clusters of microtubules. The centrioles are organized microtubules that actually help to serve as skeletal system of the cell. These centrioles help to determine the locations of the nucleus.
A keystone species helps define an entire ecosystem. Without its keystone species, the ecosystem would be dramatically different or cease to exist altogether.
Answer:
chemicals
Explanation:
The nose and the tongue are two of the five sensory organs (others being skin, eyes, ears). These organs contain certain cellular structures called SENSORY RECEPTORS, which respond to different stimulus in the environment.
Nose and tongue are two organs that possess a type of sensory receptor called CHEMORECEPTORS. Chemoreceptors are receptors that respond to chemical stimuli. In other words, the receptors in the nose and tongue are stimulated by chemical substances e.g. food chemicals for TONGUE, chemicals in air for NOSE.
Answer:HOW DO INFECTIOUS MICROORGANISMS CONTAMINATE DRINKING WATER? animal waste. Wells and other drinking water sources can be contaminated by storm water run-off from roadways, farms and livestock operations, discharges from sewage treatment plants, or septic system discharges.