Distinguish between the following pairs:
(a) Exocrine and endocrine glands (secretory substance and example)
(b) Enzymes and hormones (mode of transport and target organ)
(c) Nervous control and hormonal control (transmission and effect)
(d) Diabetes mellitus and diabetes insipidus (cause and symptoms)
(e) Addison's disease and Cushing's syndrome (cause and sugar level)
(a) Difference between exocrine and endocrine glands (secretory substance and example):
| Exocrine glands | Endocrine glands |
|---|---|
| Exocrine glands secrete their products like sweat, enzyme, mucus, sebum, saliva, milk, etc. into ducts. | Endocrine glands secrete their products, known as hormones, directly into the bloodstream. |
| Examples of exocrine glands are Sweat glands, Salivary glands, Sebaceous glands, etc. | Examples of endocrine glands are Thyroid, Pituitary, Adrenal, Pancreas. |
(b) Difference between enzymes and hormones (mode of transport and target organ):
| Enzymes | Hormones |
|---|---|
| Enzymes function intracellularly or within the confines of specific organs. They are not released into the bloodstream. | Hormones are released into the bloodstream by endocrine glands. |
| Enzymes do not have target organs. Instead, they act on their substrates at the cellular level and are highly specific for the reactions they catalyze. | Hormones have specific target organs or tissues usually away from their source. |
(c) Difference between nervous control and hormonal control (transmission and effect):
| Nervous control | Hormonal control |
|---|---|
| Effect is only short-lived. | Effect is short term or long lasting. |
| Transmitted electro-chemically through nerve fibres and chemically across synapses. | Transmitted chemically through blood. |
(d) Difference between diabetes mellitus and diabetes insipidus (cause and symptoms):
| Diabetes mellitus | Diabetes insipidus |
|---|---|
| Caused due to insufficient secretion of insulin. | Caused due to insufficient secretion of anti-diuretic hormone (ADH) |
| High concentration of sugar in blood. | No sugar in urine |
(e) Difference between Addison's disease and Cushing's syndrome (cause and sugar level):
| Addison's disease | Cushing's syndrome |
|---|---|
| Caused due to hyposecretion of cortisone | Caused due to hypersecretion of cortisone |
| Low blood sugar level | High blood sugar level |