1. sugar beets plants start from tiny seeds and grow to be large plants. where does the bulk of their mass come from? a. nutrients absorbed from the soil b. carbon dioxide taken in from the surrounding air c. sugars absorbed from the soil d. oxygen taken in from the surrounding air 2. in what part of the beet pant is the excess sucrose stored? a. root b. leaves c. stem

1.  B. carbon dioxide taken in from the surrounding air

2. A. Root

Explanation:

Sugar beet plant carries out photosynthesis and stores the excess of the sucrose in its taproots. During the process of photosynthesis, the plant absorbs CO2 from the air, water from the soil and synthesizes organic sugars in the presence of sunlight.

Atmospheric CO2 contributes carbon and oxygen atoms to the formed sugars which in turn are stored in plant parts. Therefore, atmospheric CO2 makes most of the mass of the photosynthesizing plants such as sugar beets. The taproots of beet plants are modified into storage roots to store the excess of the organic sugars.

The nervous system sends messages from nerve endings to the brain and from the brain to cells, tissues, and organs. Cells of the nervous system sometimes secrete chemical messengers instead of neurotransmitters. These specialized nervous system cells are called neurosecretory cells, and they produce neurosecretions. Every nerve cells are long, thin cylinders along which electrical disturbances (nerve impulses) travel. the cell membrane of a typical nerve cell consists of an inner and an outer wall separated by a distance of 0.10 μm and the electric field within the cell membrane is 7.0×105n/c.