Absence of thyroid hormone would result in a. increased heart rate and increased force of heart contraction, b. depression of the CNS and lethargy, c. exophthalmos, d. high metabolic rate.

Video transcript

Hi, everyone. Let's look at our next question. It says, fatigue, weakness, weight gain, cold intolerance, constipation, dry skin, hair loss, menstrual regularities in women, slow heart rate or voice, memory impairment and difficulty in concentrating are features of a dementia. B Alzheimer's disease, C hyperthyroidism or D hypothyroidism. Well, something that can help us with this question is to recall that the thyroid hormones kind of regulate the entire metabolic rate of the body. So we see we have just a whole range of symptoms in all different areas of the body. So we're definitely talking about the thyroid hormones here. Choices A and B dementia. Alzheimer's disease do involve uh memory impairment and difficulty concentrating, but that's it. They don't cause these other symptoms here. So we're going to rule them out. So we've, we're left with hyperthyroidism and hypothyroidism. Um You can sort of always remember hyper means high levels. Uh I always just think of a hyper child, high energy and hypothyroidism would be low levels of thyroid hormone. That's a little bit tricky in the case of thyroid, hyper and hyper, refer to the levels of the thyroid hormones themselves because you also have t S H thyroid stimulating hormone, which is going to be sort of reversed. But here we're talking about the thyroid hormones themselves and we're talking about symptoms. You see a lot of symptoms that involve a low metabolic rate, that would be things like fatigue, weakness, cold intolerance. Because with low metabolism, you're not generating much body heat and slow heart rate. Um the memory impairment and difficulty concentrating would reflect the effective low metabolic rate on your sort of brain activity. Uh dry skin and hair loss effects on hair and skin follicles, menstrual regularity is just effect of throwing other hormones off balance and constipation due to low intestinal motility. So a low metabolic rate reflects a low level of thyroid hormone hormones and so choice d hypothyroidism is the answer we're looking for here. So I see hyperthyroidism would cause sort of opposite symptoms. It's going to cause uh sweating from being too hot weight loss rather than weight gain, uh nervousness as a result of sort of rapid heartbeat and high metabolism. So that's why that's not a correct answer. So again, this huge range of different symptoms we have in our question, all are features of choice. The hypothyroidism, a low thyroid hormone level. See you in the next video.