Arent's Signature: Directions: Read the following item and choose the letter of the correct answer. Write your answers in your body
a. brain
d. bones
1. It is referred to as the river of life.
a. blood vessels b. heart
c. capillaries
2. It is considered as the functional unit of the nervous system.
b. neurons
c. muscles
3. It controls and coordinates the activities of the whole nervous system.
a. central nervous system b. sympathetic nervous system
c. nervous system d. brain
4. It is a system that controls other parts of the body.
a. nervous system b. circulatory system
c. digestive system
5. It is the primary organ of the central nervous system contained within the skull.
a. brain
b. axon
c. dendrites
d. cell body
d. respiratory system
Direct​

What are the three major branches of natural science? • earth and space science, life science, physical science •earth and space science, physical science, chemistry •physical science, life science, chemistry •life science, chemistry, physics

A3.37-mg sample of protein was chemically digested to convert its nitrogen into ammonia and then diluted to 100.0 ml. then 10.0 ml of this solution was placed in a 50-ml volumetric flask and treated with 5 ml of phenol solution plus 2 ml of sodium hypochlorite solution. the sample was diluted to 50.0 ml, and the absorbance at 625 nm was measured in a 1.00-cm cuvette and found to be 0.486. for reference, a standard solution was prepared from 10.0 mg of nh4cl (molar mass = 53.49 grams/mole) dissolved in 1.00 l of water. then 10.0 ml of this standard was placed in a 50-ml volumetric flask, treated in the same manner as the unknown, and the absorbance found to be 0.323. finally, a reagent blank was prepared using distilled water in place of unknown, it was treated in the same manner as the unknown, and the absorbance found to be 0.076. calculate the weight percent of nitrogen in the protein.

An experiment is conducted to see if cats preferred skim milk or 2% milk. a cup of skim milkwas put out for 5 kittens and then measured how much the kittens drank over the course of aday. following a cup of 2% milk was purout for the skittens and then masured how much thekittens drank over the course of a day. the same kittens were used and the milk was served atthe same temperature. it was discovered that the cats liked the 2% milk more than the skimmilk. what is the dependent variable in this experiment?