Darul ulo copic
1. two atoms are held together by a(n) when an
electron transfers from one atom to the other.
2. a(n) molecule can be dissolved in a water solution,
but a(n) molecule does not mix with water.
3. the ability of water to change from solid to liquid is a(n)
- of water.
4. a(n) is a tiny particle in the nucleus of an atom that
has a positive electrical charge.
5. atoms with a(n) _ share electrons.
6. a(n) of an atom has the same atomic number but a
different atomic mass.
7. a solution with a 7.0 is considered to be neutral.
8. a(n) is a group of atoms that behave like they are
one ion.
9. the number of protons in the nucleus of the atom is called
the
10. a(n) donates hydrogen ions to a solution, but a(n)
accepts hydrogen ions.
11. a(n) has no charge and is found in the nucleus.
12. anything that has mass and takes up space is
13. a solution that can receive moderate amounts of acid or
base without changing its ph is a(n)

Rease is an enzyme used by plants to break down urea (a nitrogen-containing compound) into carbon dioxide and ammonia. urease urea > > > carbon dioxide and ammonia ammonia is broken down by plants into a nitrogen source plants need to grow. thus, plants could not use urea as a nitrogen source unless it was first converted to ammonia. in soybean plants there are two different kinds of urease, one produced in the seeds and the other produced in the leaves of the plant. three types of soybean plants were used in a set of experiments: normal soybeans and two mutant strains, one lacking the urease in the seeds only (strain 1) and one lacking urease in the leaves only (strain 2). experiment 1 separate areas in a field were planted with normal, strain 1, and strain 2 soybeans. all types of soybeans appeared to grow, flower, and produce seeds equally well. there were no externally detectable differences among the strains. experiment 2 small pieces of plant leaves of equal weight were obtained from each type of soybean plant and separately placed on media in culture dishes. tissue growing in this way will become an unorganized clump of cells referred to as callus. to provide a controlled nitrogen source, half the tissue samples of each type were placed on media containing urea, and the other half of the samples were placed on media containing ammonia. after 30 days, the weight gain for each of the callus samples was determined. results are shown in the table below.