Which amine hormone acts like a steroid

These hormones cannot pass through plasma membranes of cells; therefore, their receptors are found on the surface of the target cells. An endocrinologist is a medical doctor who specializes in treating disorders of the endocrine glands, hormone systems, and glucose and lipid metabolic pathways.

An endocrine surgeon specializes in the surgical treatment of endocrine diseases and glands. Endocrinologists are required to assess patients and diagnose endocrine disorders through extensive use of laboratory tests. Many endocrine diseases are diagnosed using tests that stimulate or suppress endocrine organ functioning. Blood samples are then drawn to determine the effect of stimulating or suppressing an endocrine organ on the production of hormones. For example, to diagnose diabetes mellitus, patients are required to fast for 12 to 24 hours.

They are then given a sugary drink, which stimulates the pancreas to produce insulin to decrease blood glucose levels. A blood sample is taken one to two hours after the sugar drink is consumed. If the pancreas is functioning properly, the blood glucose level will be within a normal range.

Another example is the A1C test, which can be performed during blood screening. The A1C test measures average blood glucose levels over the past two to three months by examining how well the blood glucose is being managed over a long time. Some cases of diabetes mellitus can be managed by exercise, weight loss, and a healthy diet; in other cases, medications may be required to enhance insulin release.

If the disease cannot be controlled by these means, the endocrinologist may prescribe insulin injections. In addition to clinical practice, endocrinologists may also be involved in primary research and development activities.

For example, ongoing islet transplant research is investigating how healthy pancreas islet cells may be transplanted into diabetic patients. They control a variety of biological processes including muscle growth, heart rate, menstrual cycles and hunger. Hormones travel throughout the body, either in the blood stream or in the fluid around cells, looking for target cells.

Once hormones find a target cell, they bind with specific protein receptors inside or on the surface of the cell and specifically change the cell's activities. The protein receptor reads the hormone's message and carries out the instructions by either influencing gene expression or altering cellular protein activity.

These actions produce a variety of rapid responses and long-term effects. Hormones vary in their range of targets. Some types of hormones can bind with compatible receptors found in many different cells all over the body. Other hormones are more specific, targeting only one or a few tissues. For example, estrogens, the female sex hormones, can regulate function by binding to special estrogen receptor sites in uterine, breast and bone cells.

In addition, the same cell can act as a target cell for many different regulatory molecules. Chapter Biotechnology. Chapter Viruses.

Chapter Nutrition and Digestion. Chapter Nervous System. Chapter Sensory Systems. Chapter Musculoskeletal System. Chapter Circulatory and Pulmonary Systems. Chapter Osmoregulation and Excretion. Chapter Immune System. Chapter Reproduction and Development. Chapter Behavior. Chapter Ecosystems. Chapter Population and Community Ecology. Chapter Biodiversity and Conservation. Chapter Speciation and Diversity.

Chapter Natural Selection. Chapter Population Genetics. Chapter Evolutionary History. Chapter Plant Structure, Growth, and Nutrition. Chapter Plant Reproduction. Chapter Plant Responses to the Environment. Full Table of Contents. This is a sample clip. Sign in or start your free trial. JoVE Core Biology. Previous Video Next Video. Embed Share. Peptide hormones : The structures of peptide hormones a oxytocin, b growth hormone, and c follicle-stimulating hormone are shown.

These peptide hormones are much larger than those derived from cholesterol or amino acids. Secreted peptides, such as insulin, are stored within vesicles in the cells which synthesize them. They are then released in response to stimuli e. Amino acid-derived and polypeptide hormones are water-soluble and insoluble in lipids.

These hormones cannot pass through plasma membranes of cells; therefore, their receptors are found on the surface of the target cells. Privacy Policy. Skip to main content. The Endocrine System. Search for:. Types of Hormones. Hormone Functions The endocrine system plays a role in growth, metabolism, and other processes by releasing hormones into the blood. Learning Objectives Evaluate hormones and their purpose in the body.

Key Takeaways Key Points Hormones serve as chemical messengers in the body and help maintain homeostasis. Hormones are released into bodily fluids, like blood, which carry them to target cells.