Which one of the following is NOT true of human hormones?
A. They are all released from glands and flow down ducts into the bloodstream.
B. A hormone may affect one or more structures in the body.
C. They travel at the speed of blood flow.
D. They are all chemicals.
E. Some, such as testosterone and oestrogen, can be steroids.
The answer to this question is A. This is a bit of a tricky question, and needs full attentiveness to how the choices were formulated/worded.
Choices B - E: These all are correctly associated with human hormones. Basically, hormones are chemicals which act as the messengers of the signalling system of the body to induce different functions of different organs. They are released into the bloodstream where they are carried to the various tissues and organs.
Why is choice A not correctly associated with human hormones? There are 2 main reasons why choice A is wrong.
This is the tricky part of the question. On first glance, it might be tempting to see this choice as a correct description of hormones, but as you observe carefully, the choice includes the word “all”. This is false since not all hormones are released from glands. Yes, even though it is true that most of what secretes hormones are glands, like the pancreas, adrenals, pituitary, parathyroid, thyroid, and pineal gland, there are still other structures in the body that are also responsible for secreting these chemical messengers. These include the kidneys that release hormones involved in maintaining blood pressure. Ovaries and testes also produce hormones that function to maintain our sexual characteristics.
The second main reason why this choice is wrong is because of its inclusion of “ducts”. This is false because endocrine glands or those organs that release hormones do not need ducts to carry their hormonal secretions to the bloodstream, since the hormones are released directly into the bloodstream. These hormones will now then be carried in the blood to the various organs that it was intended for.
In summary, it is very important that you read the question and their choices very carefully. They might seem correct at the first glance, but do check how they were worded.