Answer:
From this it can be deduced that the fresh water is hypotonic and the salt solution is hypertonic to the cells of the celery stalks.
Explanation:
When submerged in water, the celery stalks become stiff and hard, this shows that water moves within the stalk, thus, water is hypotonic in comparison to the celery stalk. Therefore, water moves from the region of higher concentration to the region of lower concentration.
When the same celery stalk is administered into the 0.15 M solution it turns soft, which shows that water from the celery stalk moves out. Thus, the salt solution is hypertonic in comparison to the celery stalk. Therefore, freshwater is hypertonic and the solution of salt is hypertonic to the celery stalk cells.
Out of the following given choices;
A. theory that fish and mammals have a common ancestry
B. theory that the first organisms on Earth were heterotrophs
C. close relationship between fish and mammalian reproductive patterns
D. close relationship between humans and annelids
The answer is A. Many embryos of the kingdom Animalia share similarities in the early stages depicting that they share a common ancestor. The gill slits is one example. They diverge in later stages to become Pharyngeal in the human embryo, while they differentiate into gills in fish.
Answer:
Option A, a drug to treat high blood pressure that reversibly inhibits an enzyme catalyzing production of a chemical that causes blood vessels to contract
Explanation:
The complete question is
If you were working for a pharmaceutical company as part of a drug discovery team, which of these enzyme inhibitors would you suggest as a productive avenue for drug development?
a) a drug to treat high blood pressure that reversibly inhibits an enzyme catalyzing production of a chemical that causes blood vessels to contract
b) a drug to treat diabetes that irreversibly inhibits an enzyme in the metabolic pathway to synthesize glucose
c) a compound that acts as a competitive inhibitor for a digestive enzyme produced only in the presence of certain foods
d) a compound that inhibits enzymes by significantly changing the ph throughout the body
Solution
Productive avenue of a drug simply means producing an drug that not only treats the main disease or disorder but also functions to inhibit the causative agent activity. In case of option A, both the objectives of producing drug are met and hence it is the right choice.
High blood pressure usually affects the blood vessels by narrowing them and in severe cases may rupture them. If a drug as stated in option A is produced, it will not only rectify the effects of high blood pressure but will also prevent the blood vessels from narrowing by inhibiting the activity of enzymes responsible for producing chemical that leads to blood vessel contraction.
Hence, option A is correct
