If no oxygen is present, pyruvic acid breaks down to form lactic acid. you can feel the effects of lactic acid if you exercise very hard. one way to produce lactic acid is to do a "wall sit," supporting yourself against a wall in a sitting position. try doing this for a few minutes. what do you feel in your thigh muscles?

You would feel thigh muscle pain.

Explanation:

Lactic acid occurs when the muscle gets energy without oxygen and can cause immense pain in the muscle. This occurs when the muscle is subjected to extreme exertion, which the muscle is not used to. This pain comes with a feeling of muscle fatigue and intense burning.

If you did the wall sit position your thigh muscles would be making an intense effort to maintain that position. There would probably be the release of lactic acid into the muscles of your thigh causing pain, fatigue and a burning sensation.

the answer is admiramos

the rule for verbs is whoever you are referring to (in this case 'nosotros'), you need to change the ending of the word.

nosotros - amos

yo - o

tu - as

el, ella, usted - a

ellos, ellas, ustedes - an

(examples: nosotros bailamos (instead of bailar) or yo hablo (instead of habla)

cells use diffusion to get substances in and out of themselves. that diffusion will occur across the cell membrane or the outer covering of the cell. because we are talking about the surface of the cell, surface area and volume are  important factors here. as a cell increases in size, its surface area and volume increase as well.  we call that the surface area to volume ratio (sa: vol).  but the catch is that  volume increases at a greater rate than surface  area. in other words, as a cell gets bigger, the sa: vol gets smaller. so a really small cell like bacteria is mostly cell membrane (surface) with very little contents (volume). a really big cell like an egg, is mostly insides with a super thin membrane. so what ends up happening is that the cell cannot efficiently diffuse all of the stuff it needs in/out to survive. therefore cell size is limited to about 100mm. so how do we make organisms bigger than 100mm? cells divide! by dividing and becoming multicellular, organisms are able to grow!   check out the diagrams i attached to see the effect of sa: vol. i hope this ! good luck!