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What are the lobes of the thyroid gland?

What are the lobes of the thyroid gland?

The thyroid gland lies in the front of your neck in a position just below your Adam’s apple. It is made up of two lobes – the right lobe and the left lobe, each about the size of a plum cut in half – and these two lobes are joined by a small bridge of thyroid tissue called the isthmus.

How many lobes are present in the thyroid?

Anatomy Overview The thyroid gland is divided into two lobes that are connected by the isthmus, which crosses the midline of the upper trachea at the second and third tracheal rings.

What are thyroid follicles made of?

The follicles are made up of a central cavity filled with a sticky fluid called colloid. Surrounded by a wall of epithelial follicle cells, the colloid is the center of thyroid hormone production, and that production is dependent on the hormones’ essential and unique component: iodine.

What are thyroid cells?

Thyroid cells are the only cells in the body which can absorb iodine. These cells combine iodine and the amino acid tyrosine to make T3 and T4. T3 and T4 are then released into the blood stream and are transported throughout the body where they control metabolism (conversion of oxygen and calories to energy).

What does T3 and T4 do?

T3 and T4 work together to regulate how your body uses energy. These hormones also play an important role in controlling your weight, body temperature, muscle strength, and nervous system.

How is T3 and T4 produced?

Thyroid hormones (T4 and T3) are produced by the follicular cells of the thyroid gland and are regulated by thyroid-stimulating hormone secreted by the anterior pituitary gland.

Which type of epithelium is present in thyroid follicles?

Thyroid follicular cells form a simple cuboidal epithelium and are arranged in spherical thyroid follicles surrounding a fluid filled space known as the colloid.

What hormone is made by the parafollicular cells of the thyroid gland?

Calcitonin is secreted by the parafollicular cells of the thyroid gland. This hormone opposes the action of the parathyroid glands by reducing the calcium level in the blood.

What are the cells in between the follicles called?

Inbetween the follicles are the parafollicular cells, also known as C-cells. They secrete two hormones that influence the rate of metabolism[23]: T3 (tri-iodothyronine) and. T4 (tetra-iodothyronine or thyroxine)

What are follicular cells in the thyroid?

Thyroid follicular cells (also called thyroid epithelial cells or thyrocytes) are the major cell type in the thyroid gland, and are responsible for the production and secretion of the thyroid hormones thyroxine (T4) and triiodothyronine (T3).

Where is T3 and T4 produced?

The thyroid gland is essential to the endocrine system. It is located in front of the neck and is responsible for the production of thyroid hormones. The thyroid gland releases triiodothyronine (T3) and thyroxine (T4).