Please answer question
1 answer:
You might be interested in
Answer:
Hormone production and release are primarily controlled by negative feedback. In negative feedback systems, a stimulus elicits the release of a substance; once the substance reaches a certain level, it sends a signal that stops further release of the substance. In this way, the concentration of hormones in blood is maintained within a narrow range. For example, the anterior pituitary signals the thyroid to release thyroid hormones. Increasing levels of these hormones in the blood then give feedback to the hypothalamus and anterior pituitary to inhibit further signaling to the thyroid gland, as illustrated in Figure 18.14. There are three mechanisms by which endocrine glands are stimulated to synthesize and release hormones: humoral stimuli, hormonal stimuli, and neural stimuli.
Explanation:
Hyperthyroidism is a condition in which the thyroid gland is overactive. Hypothyroidism is a condition in which the thyroid gland is underactive. Which of the conditions are the following two patients most likely to have?
Patient A has symptoms including weight gain, cold sensitivity, low heart rate and fatigue.
Patient B has symptoms including weight loss, profuse sweating, increased heart rate and difficulty sleeping.Humoral Stimuli
The term “humoral” is derived from the term “humor,” which refers to bodily fluids such as blood. A humoral stimulus refers to the control of hormone release in response to changes in extracellular fluids such as blood or the ion concentration in the blood. For example, a rise in blood glucose levels triggers the pancreatic release of insulin. Insulin causes blood glucose levels to drop, which signals the pancreas to stop producing insulin in a negative feedback loop.
Hormonal stimuli refers to the release of a hormone in response to another hormone. A number of endocrine glands release hormones when stimulated by hormones released by other endocrine glands. For example, the hypothalamus produces hormones that stimulate the anterior portion of the pituitary gland. The anterior pituitary in turn releases hormones that regulate hormone production by other endocrine glands. The anterior pituitary releases the thyroid-stimulating hormone, which then stimulates the thyroid gland to produce the hormones T3 and T4. As blood concentrations of T3 and T4 rise, they inhibit both the pituitary and the hypothalamus in a negative feedback loop.
Answer:
This question lacks options, the options are:
A) FF and ff
B) FF and Ff
C) Ff and Ff
D) Ff and ff
The answer is D (Ff and ff for parent 1 and 2 respectively)
Explanation:
This question depicts a single gene coding for fur colour in mice. The gene controls two traits, black fur and white fur, encoded by alleles F and f respectively.
According to the question, a pair of mice has been bred several times to generate the same data of 22 black fur and 23 white fur mice. Based on this data, it shows that the phenotypic ratio of black to white mice is 1:1.
To get a 1:1 phenotypic ratio of black fur offspring to white fur offspring, the parents mice must have genotypes Ff (heterozygous) and ff (same recessive alleles).
In a cross between parents Ff × ff (see punnet square), offsprings with the following genotypes will be produced: Ff, Ff, ff and ff. Ff is black furred while ff is white furred.
Ff (2) : ff (2) is equivalent to Ff (1) : ff (1).
Hence, a data of 22 black mice and 23 white mice which represents a 1:1 ratio will only be produced by parents mice with genotypes: Ff and ff.
