Boiling point. If you boil water it changes from a liquid to a gas, which is a physical change. The rest are chemical properties because the chemical make up of an object changes.
The correct answer is: B) continuous transcription of the structural gene controlled by that regulator
A regulatory gene is gene that encodes for a protein, such as a repressor (or activators) that controls the transcription of another gene or group of genes.
The regulatory gene of a repressible operon encodes for the repressor that inhibits gene transcription. So, when that repressor isn’t active, transcription occurs continuously.
I think the first one is right !.... but the for the other one it's B .
The answer is epididymis.
<span>Testicles contain seminiferous tubules, in which sperm is produced, and an epididymis, in which sperm matures. Mature sperm passes through the epididymis to the vas deferens. There, it combines with a liquid secretion from the seminal vesicles and continues through the prostate gland to the urethra. Sperm containing fluid is called semen and it is ejected through the urethra.</span>