Have you ever noticed the changes that take place in your body as you approach puberty? In male, broader shoulders, more bulky and developed muscles, growth of facial hair and deepening of voice is observed; while development of breasts, onset of monthly menstrual cycles, growth of pubic hairs are some of the common changes that are reported in females approaching puberty. All these changes are a result of certain glands and their secretions, released in the body.

Glands are specialized organs which release chemicals in small doses (generally known as hormones). These glands can be divided into two main types namely endocrine and exocrine glands. A lot of people want to know the difference between endocrine and exocrine glands in terms of physiology and pathology.

What Are Endocrine and Exocrine Glands?

Before figuring out the difference between endocrine and exocrine glands, it is very important to understand the basic functions and locations of these hormones.

Endocrine Glands

Endocrine glands are specialized organs which release their chemicals directly into cells or surrounding tissues.The released chemicals of the endocrine system help in regulation and maintenance of multiple physiological events, such as body metabolism, menstrual flow and uterine changes, reproductive functioning, etc.

Components: Endocrine glands include thyroid and parathyroid gland, pineal gland, testes and ovaries, pituitary gland, pancreas, hypothalamus and adrenal glands, etc.

Exocrine Glands

Exocrine glands are specialized secretions which are released through a duct directly into an external or internal surface such as sebaceous glands, mammary glands, mucus producing glands.The secretions produced by exocrine glands help in the regulation of multiple phenomena such as regulation of body temperature through sweat glands. Likewise, the lacrimal glands in the eyes help preventing the eyes from dying out.

Components: Typical exocrine glands are salivary glands, sweat glands, mammary glands, digestive system glands.

Pancreas and liver are the twoorgans that crossover both exocrine and endocrine glands.

Difference Between Endocrine and Exocrine Glands

You may get some idea of differences the two glands from the above mentioned definitions and functions. Some key differences between endocrine and exocrine glands are listed as below:

1. Ducts

• Endocrine glands do not utilize ducts or tubes to release their secretions, while exocrine glands require some ducts for transportation of their secretions.
• For this reason the exocrine glans are classified into two types according to the duct types:
• Simple exocrine gland: This has only one single duct or unbranched simple ducts for transportation of released substances.
• Compound exocrine gland: They consist of multiple branches of the duct which are secondary and tertiary branches responsible for releasing the substance at the targeted site.

2. Response Time

Response time can be one of the factors of difference between endocrine and exocrine glands.

• The response of the endocrine glands is generally delayed due to the release of substances in the blood which then transported to the target tissues.
• Exocrine glandular secretion however possesses a quicker response time as they are released directly at the target site.

3. Duration of Action

Although the response time of endocrine glands is longer than that of exocrine glands, the secretions of endocrine glands have longer duration of act. This happens because the blood containing released substances is passed from kidneys for the purpose of filtration where they are reabsorbed and again transported to the target site. On the contrary, the secretions of exocrine glands are not passed to kidney so there is no reabsorption hence the duration or effect is shorter.

4. Other Differences Between Exocrine and Endocrine Glands

Below is a summarized comparison between endocrine and exocrine glands:

Pathological Significance

Knowing the difference between endocrine and exocrine glandshelps with a better understanding as to what is normal and what is diverted from the normal physiology. Crying and sweating are short term phenomenon and usually stops after some time but if such secretions persists for a longer period of time (such as constant sweating or lacrimal fluid) then it indicates that a person is suffering from some pathological condition.