Related Concept Videos

Disorders of the Female Reproductive System01:24

Disorders of the Female Reproductive System

The female reproductive system can be affected by several disorders, including Premenstrual Syndrome (PMS), Premenstrual Dysphoric Disorder (PMDD), endometriosis, and various forms of cancer. PMS and PMDD are cyclical conditions that cause physical and emotional distress, with symptoms that include edema, mood swings, and food cravings. PMDD is a more severe form of PMS characterized by increased symptom severity that peaks during the luteal phase and tends to improve or resolve shortly after...
Hyperthyroidism II: Pathophysiology01:27

Hyperthyroidism II: Pathophysiology

Hyperthyroidism is a hypermetabolic state caused by elevated levels of thyroid hormones, triiodothyronine (T3) and thyroxine (T4). It results from dysregulation at the thyroid, pituitary, or immune system level and affects multiple organ systems.PathophysiologyThe most common cause of hyperthyroidism is Graves’ disease, an autoimmune disorder in which antibodies, specifically thyroid-stimulating antibodies (TSAb), a subtype of TSH receptor antibodies (TRAb), bind to and activate TSH receptors...
Cellular Adaptation III: Hyperplasia01:26

Cellular Adaptation III: Hyperplasia

Hyperplasia is an increase in the number of cells in a tissue or organ due to enhanced cell division. It is an adaptive, controlled response to stimuli such as injury, hormones, or stress, involving mitosis to produce genetically identical cells and support tissue repair and regeneration.Tissue CapacityCertain tissues, including the epidermis, intestinal epithelium, bone marrow, and fibroblasts, have a high potential for hyperplasia. Others, such as bone, cartilage, and smooth muscle, show...
Cellular Adaptation IV: Dysplasia and Metaplasia01:24

Cellular Adaptation IV: Dysplasia and Metaplasia

DysplasiaDysplasia refers to abnormal changes in the size, shape, and organization of mature cells, characterized by pleomorphism, nuclear abnormalities, and increased mitotic activity. It commonly affects epithelial tissues, including the cervix, gastrointestinal tract, respiratory mucosa, and endometrium. Although it may occur alongside hyperplasia, dysplasia is not a true adaptive response but a preneoplastic change with potential to progress to cancer.When confined above the basement...
Target Cell Response to Hormones01:22

Target Cell Response to Hormones

Hormones intricately bind to receptors on the surface or within target cells, initiating a cascade of cellular responses.
Notably, the cellular response can be regulated by altering the number of receptors expressed in the cell. For example, prolonged exposure to elevated hormone levels results in a gradual decline or down-regulation in the number of receptors for that specific hormone on the cell surface. Conversely, in response to low hormone levels, cells may use up-regulation, producing an...
Hyperthyroidism I: Introduction01:25

Hyperthyroidism I: Introduction

Hyperthyroidism is a type of thyrotoxicosis characterized by the thyroid gland's overproduction of the thyroid hormones triiodothyronine (T3) and thyroxine (T4). This hormone excess increases the basal metabolic rate and enhances sensitivity to catecholamines.DiagnosisDiagnosis is based on clinical features and biochemical testing. It typically shows suppressed thyroid-stimulating hormone (TSH) levels below 0.4 mIU/L, with elevated free T3 and/or T4. Additional tests, including thyroid...