Ambo university college of medical and health science

tilahun reference

✅ HORMONES PRODUCED BY OTHER ORGANS & TISSUES THAT CONTAIN ENDOCRINE CELLS & THEIR PRINCIPAL ACTIONS ✅ 🎬GASTROINTESTINAL TRACT 🔵 Gastrin Promotes secretion of gastric juice; increases movements of the stomach. 🔵 Glucose-dependent insulinotropic peptide (GIP) Stimulates release of insulin by pancreatic beta cells. 🔵 Secretin Stimulates secretion of pancreatic juice and bile. 🔵 Cholecystokinin (CCK) Stimulates secretion of pancreatic juice; regulates release of bile from gall bladder; causes feeling of fullness after eating. 🎬 PLACENTA 🔵 Human chorionic gonadotropin (hCG) Stimulates corpus luteum in ovary to continue production of oestrogens and progesterone to maintain pregnancy. 🔵 Oestrogens and progesterone Maintain pregnancy; help prepare mammary glands to secrete milk. 🔵 Human chorionic somatomammotropin (hCS) Stimulates development of mammary glands for lactation. 🎬 KIDNEYS 🔵 Renin Part of reaction sequence that raises blood pressure by bringing about vasoconstriction and secretion of aldosterone. 🔵 Erythropoietin (EPO) Increases rate of red blood cell formation. 🔵 Calcitriol (active form of vitamin D) Aids in absorption of dietary calcium and phosphorus. 🎬 HEART 🔵 Atrial natriuretic peptide (ANP) Decreases blood pressure. 🎬 ADIPOSE TISSUE 🔵 Leptin Suppresses appetite; may increase FSH and LH activity.

⭕️Endoplasmic Reticulum⭕️ (1) Definition: It is well developed electron microscopic network of interconnected cisternae, tubules and vesicles present throughout the cytoplasm, especially in the endoplasm. (2) Discovery: Garnier (1897) was first to observe the ergastoplasm in a cell. The ER was first noted by Porter, Claude, and Fullman in 1945 as a network. It was named by Porter in 1953. Golgi Complex (1) Definition: Golgi complex is made up of various membranous system e.g. cisternae, vesicles and vacuoles. (2) These are also called golgi bodies, golgisomes, lipochondrion, dictyosomes, Dalton complex, idiosomes or Baker’s body. (3) These are also called “traffic police” of the cell. (4) Discovery: First observed by George (1867) but it’s morphological details were given by Camillo Golgi (1898), in nerve cells of barn fowl and cat .

Burn is a term used to describe the injury caused by heat, electricity, chemicals, or radiation. Burns can be classified into three phases: the acute phase, the intermediate phase, and the rehabilitative phase. The acute phase is the initial stage of a burn injury and lasts for the first 72 hours. During this phase, the priority is to stabilize the patient's condition and prevent further damage. The patient may experience shock, pain, swelling, and fluid loss during this phase. Treatment includes wound cleaning, pain management, and fluid replacement therapy. The intermediate phase begins after the first 72 hours and lasts until the wound is healed. During this phase, the focus is on wound care and preventing infection. The wound is cleaned regularly, and dressings are changed to promote healing. The patient may also undergo physical therapy to maintain range of motion and prevent scarring. The rehabilitative phase begins once the wound has healed. The focus is on restoring function and improving quality of life. This may include scar management, cosmetic procedures, and psychological support. It is important to note that the severity of a burn injury can vary widely, and treatment will depend on the extent and depth of the burn. In some cases, surgery may be necessary to remove damaged tissue and promote healing. Burn injuries can have long-term physical and emotional effects, so ongoing support and care may be needed even after the wound has healed.

Immunoglobulins, also known as antibodies, are proteins produced by the immune system in response to the presence of foreign substances, such as bacteria or viruses. They are Y-shaped molecules that have two functional regions: the variable region, which recognizes and binds to specific antigens on pathogens, and the constant region, which mediates various immune responses. There are five main types of immunoglobulins: IgG, IgM, IgA, IgD, and IgE. Each type has a distinct structure and function in the immune response. Immunoglobulin G (IgG) is the most abundant type in the body and provides long-term immunity against pathogens. It can neutralize toxins produced by bacteria and viruses, enhance phagocytosis (the engulfing and destruction of pathogens by immune cells), and activate complement proteins to destroy pathogens. Immunoglobulin M (IgM) is the first antibody produced during an initial immune response. It is effective at neutralizing pathogens and activating other components of the immune system, such as phagocytes and complement proteins. Immunoglobulin A (IgA) is found in high concentrations in mucosal areas, such as the respiratory and gastrointestinal tracts. It plays a vital role in preventing infections at these sites by neutralizing pathogens and preventing their attachment to mucosal surfaces. Immunoglobulin D (IgD) is less understood compared to other immunoglobulins. It is believed to play a role in the activation of B cells, which are responsible for producing antibodies. Immunoglobulin E (IgE) is involved in allergic reactions and defense against parasites. It triggers the release of histamine, causing symptoms such as itching, inflammation, and mucus production. Immunoglobulins work by binding to specific antigens on pathogens, marking them for destruction by other immune cells or neutralizing their harmful effects directly. They can also activate other components of the immune system, such as complement proteins, to enhance the immune response. Measuring immunoglobulin levels through blood tests can help diagnose and monitor certain conditions, including autoimmune disorders, allergies, and infections. Abnormal levels of specific immunoglobulins can indicate an underlying health issue. In summary, immunoglobulins are crucial proteins produced by the immune system to defend the body against infections and foreign substances. They have diverse functions and play a vital role in maintaining overall health and well-being.

Neurophysiology - Neurophysiology is the study of the functioning and activities of the nervous system. - It focuses on understanding how nerve cells (neurons) communicate with each other and how the brain and spinal cord process and transmit information. - The nervous system is composed of two main types of cells: neurons and glial cells. Neurons are responsible for transmitting electrical signals, while glial cells provide support and protection to neurons. - Neurons communicate through electrical impulses called action potentials. These impulses travel along the neuron's axon, which is covered by a myelin sheath that speeds up the transmission. - Synapses are the junctions between neurons where chemical signals, known as neurotransmitters, are released to transmit information from one neuron to another. - Neurotransmitters can have either excitatory or inhibitory effects on the receiving neuron, influencing whether it will generate an action potential or not. - The brain and spinal cord form the central nervous system, while the nerves that extend throughout the body make up the peripheral nervous system. - The central nervous system controls and coordinates all bodily functions, while the peripheral nervous system carries information to and from the central nervous system. - Different regions of the brain are responsible for specific functions. For example, the frontal lobe is involved in decision-making and problem-solving, while the occipital lobe processes visual information. - Neurophysiology also explores the mechanisms underlying various neurological disorders, such as Alzheimer's disease, Parkinson's disease, epilepsy, and multiple sclerosis. - Techniques such as electroencephalography (EEG), functional magnetic resonance imaging (fMRI), and single-unit recording are used to study brain activity and understand neurophysiological processes. - Understanding neurophysiology is crucial for advancing knowledge in fields like neuroscience, psychology, and medicine. It helps researchers and healthcare professionals develop treatments for neurological disorders and improve overall brain health.

- The lymphatic system is a network of tissues and organs that help rid the body of toxins, waste, and other unwanted materials. - It consists of lymphatic vessels, lymph nodes, the spleen, thymus, and tonsils. - Lymphatic vessels are similar to blood vessels but carry a clear fluid called lymph instead of blood. - Lymph nodes are small, bean-shaped structures that filter lymph and contain immune cells that help fight infections. - The spleen is the largest lymphatic organ and filters blood, removing old or damaged red blood cells and storing platelets. - The thymus is located in the chest and plays a crucial role in the development and maturation of T-cells, which are important for immune response. - Tonsils are small masses of lymphoid tissue located in the back of the throat that help trap and filter bacteria and other pathogens. - The lymphatic system works in close coordination with the circulatory system to maintain fluid balance and defend against infections. - Lymph is formed from interstitial fluid that is collected by lymphatic vessels and transported back into the bloodstream. - Lymph nodes play a vital role in the immune response by filtering lymph and activating immune cells to fight off infections. - Lymphatic vessels also play a role in the absorption of fats from the digestive system, transporting them to the bloodstream. - The lymphatic system can be affected by various diseases and conditions, including lymphedema (swelling due to impaired lymphatic drainage), lymphoma (cancer of the lymph nodes), and infections such as lymphangitis or cellulitis.

Virology is a branch of microbiology that focuses on the study of viruses. Viruses are microscopic infectious agents that can only replicate inside the cells of living organisms. They are much smaller than bacteria and can cause a wide range of diseases in humans, animals, and plants. The field of virology encompasses several areas of study, including the classification and identification of viruses, their structure and replication mechanisms, their interactions with host cells, and their role in causing diseases. Virologists use various techniques and tools to study viruses, such as electron microscopy, molecular biology techniques, and cell culture systems. One of the key areas of interest in virology is the understanding of viral pathogenesis. Viruses can enter host cells, hijack their machinery, and replicate, leading to the destruction of the infected cells and the spread of the virus throughout the body. Understanding the molecular mechanisms by which viruses cause diseases is crucial for developing antiviral therapies and vaccines. Virology also plays a significant role in public health and epidemiology. Virologists study the transmission dynamics of viruses, their ability to evolve and develop drug resistance, and the factors that contribute to outbreaks and epidemics. This knowledge is essential for designing effective control measures and preventing the spread of viral infections. Furthermore, virology has important applications in biotechnology and gene therapy. Viruses can be engineered to deliver therapeutic genes to target cells, offering potential treatments for genetic disorders and certain types of cancer. Virologists also study the use of viruses as tools for gene editing and the development of viral vectors for vaccine production. Advances in virology have led to significant breakthroughs in medicine and public health. The development of vaccines against viral diseases, such as polio, measles, and influenza, has saved millions of lives. Antiviral drugs have been developed to treat infections caused by specific viruses, such as HIV and hepatitis C. Virologists continue to work on new antiviral strategies and the development of broad-spectrum antiviral agents. In conclusion, virology is a fascinating field that explores the world of viruses and their impact on living organisms. By studying viruses, virologists contribute to our understanding of viral diseases, public health, and the development of new treatments and preventive measures. Their research is essential for protecting human and animal health.

Skin is the largest organ in the human body and plays a vital role in protecting us from external threats. It acts as a barrier, shielding our internal organs from harmful substances, UV radiation, and pathogens. Moreover, skin also helps in regulating body temperature, maintaining hydration, and providing sensory information. The skin is composed of three layers: the epidermis, dermis, and hypodermis. The epidermis is the outermost layer and primarily functions as a protective shield. It consists of several layers of cells, including keratinocytes, which produce a tough protein called keratin that gives the skin its strength and flexibility. The epidermis also contains melanocytes, which produce melanin, the pigment responsible for skin color and protection against UV radiation. Beneath the epidermis lies the dermis, which is made up of connective tissue, blood vessels, hair follicles, sweat glands, and nerve endings. The dermis provides structural support to the skin and houses various components that contribute to its overall health and function. Collagen and elastin fibers in the dermis give the skin its elasticity and firmness. The hypodermis, also known as the subcutaneous tissue, is the deepest layer of the skin. It consists of fat cells that act as insulation, providing cushioning and energy storage. The hypodermis also helps in regulating body temperature by insulating against heat loss. Skin health is influenced by various factors such as genetics, age, diet, lifestyle choices, and environmental factors. Proper skincare practices are essential to maintain healthy skin. This includes cleansing to remove dirt and impurities, moisturizing to prevent dryness and maintain hydration, and protecting the skin from sun damage through the use of sunscreen. Skin conditions can range from minor issues like acne and dryness to more severe conditions such as eczema, psoriasis, and skin cancer. These conditions can cause discomfort, pain, and affect a person's self-esteem. Seeking medical advice from a dermatologist is crucial for proper diagnosis and treatment. It is important to note that skin health reflects overall well-being. Poor nutrition, lack of sleep, stress, and exposure to pollutants can negatively impact the skin. Therefore, maintaining a healthy lifestyle, including a balanced diet, regular exercise, stress management, and adequate sleep, is essential for optimal skin health. In conclusion, the skin is a remarkable organ that serves as our body's first line of defense. It not only protects us from external threats but also plays a significant role in our appearance and overall well-being. Taking care of our skin through proper skincare practices and a healthy lifestyle is crucial for maintaining its health and vitality. The skin is of utmost importance for several reasons: 1. Protection: The skin acts as a protective barrier, shielding our internal organs from harmful substances, UV radiation, and pathogens. It prevents the entry of bacteria, viruses, and other microorganisms into our body. 2. Regulation of body temperature: The skin helps regulate body temperature by sweating and dilating or constricting blood vessels. It allows heat to escape from the body when it's hot and conserves heat when it's cold. 3. Sensory perception: The skin contains nerve endings that allow us to feel sensations such as touch, pressure, pain, and temperature. It provides us with information about our environment and helps us respond appropriately. 4. Hydration: The skin helps maintain hydration by preventing excessive water loss through evaporation. It acts as a barrier to retain moisture and prevent dryness. 5. Appearance: The skin plays a significant role in our appearance. Clear, healthy skin contributes to our self-esteem and confidence. 6. Vitamin D synthesis: The skin produces vitamin D when exposed to sunlight. Vitamin D is essential for calcium absorption, bone health, and overall immune function.