Anatomy and Biology PDF Summary

ummary outlines for Bio #1_1 Anatomical Terminology Overview: Anatomical terminology is a standardized language used by healthcare professionals to accurately describe the position and relationships of body structures. It provides a common frame of reference, ensuring clear com...

ummary outlines for Bio #1_1 Anatomical Terminology Overview: Anatomical terminology is a standardized language used by healthcare professionals to accurately describe the position and relationships of body structures. It provides a common frame of reference, ensuring clear communication in anatomical and medical contexts. It includes terms related to anatomical position, direction, planes, and regions. Anatomical Position: o Reference stance: Body erect, feet slightly apart, palms facing forward. o Provides a standard frame of reference for anatomical descriptions. Anatomical Direction: o Describes the location of structures relative to others. o Common terms: superior (above), inferior (below), anterior (front), posterior (back), lateral (away from the midline), medial (towards the midline). o Proximal: Closer to the point of attachment or origin. o Distal: Farther from the point of attachment or origin. Planes of the Body: o Coronal (Frontal) Plane: Divides the body into anterior (front) and posterior (back) sections. o Transverse (Cross-Sectional) Plane: Divides the body into superior (top) and inferior (bottom) sections. o Sagittal (Median) Plane: Divides the body into left and right sections. Regional Terms: o Designate specific areas of the body for precise location. o Examples: ▪ Dorsal: Relating to the back  ▪ Lumbar: Relating to the lower back ▪ Umbilical: Relating to the navel ▪ Crural: Relating to the shin ▪ Orbital: Relating to the eye region ▪ Patellar: Relating to the front of the knee ▪ Oral: Relating to the mouth ▪ Nasal: Relating to the nose ▪ Buccal: Relating to the cheek ▪ Ocular: Relating to the eye ▪ Occipital: Relating to the back of the head ▪ Digital/Phalangeal: Relating to the fingers or toes Respiratory System Overview: The respiratory system facilitates gas exchange, primarily oxygen intake and carbon dioxide removal. Key components include the lungs, trachea, bronchi, bronchioles, and alveoli, all working together to ensure efficient ventilation and respiration. The heart's pulmonary system transports oxygen and carbon dioxide throughout the body. Lung Anatomy: o Lungs: Located in the thoracic cavity, protected by a double membrane called the pleura. ▪ Right lung: Has three lobes (superior, middle, and inferior). Larger than the left lung because the mediastinum, where the heart is located, allows the right lung more space. ▪ Left lung: Has two lobes (superior and inferior). o Trachea: Connects the larynx to the lungs (aka the windpipe). o Bronchi: The main passageways directly attached to the lungs. o Bronchioles: Smaller tubes that branch from the bronchi, connecting them to alveoli. o Alveoli: ▪ Tiny air sacs are the sites of gas exchange. ▪ Type I alveolar cells: Form the alveolar wall.  ▪ Type II alveolar cells: Release surfactant (a lipoprotein that reduces surface tension). o Mediastinum: Area between the two lungs where the heart is located. Ventilation: o Definition: Exchange of oxygen with carbon dioxide in the lungs. o Mechanism: Combination of muscle action and negative pressure. ▪ Diaphragm and intercostal muscles contract to increase lung volume, decreasing pressure and drawing air in. Relaxation of these muscles reduces lung volume, increases pressure, and expels air. o Process: ▪ Periodic inspiration: Inhalation of air. ▪ Periodic expiration: Expulsion of air. o Tidal Volume: The amount of air breathed in and out during a normal breath. Gas Exchange: o Location: Alveoli. o Process: Diffusion (passive transport from high to low concentration). ▪ Oxygen diffuses into the blood capillaries, and carbon dioxide diffuses into the alveoli. o Factors Influencing Diffusion Rate: ▪ Proportional to the surface area involved and the concentration gradient. ▪ Inversely proportional to the distance between solutions. o Capillaries: Small vessels that connect smaller arteries (arterioles) to smaller veins (venules) and carry out gas exchange.  Alveoli: o Definition: Tiny air sacs in the lungs where exchange of oxygen and carbon dioxide takes place. o Cell Types: Type I (alveolar wall) and Type II (surfactant release). o Surfactant: Reduces surface tension to prevent alveolar collapse. o Concentration Gradients: High levels of oxygen and a low concentration of carbon dioxide. Breathing Mechanics: o Role of Diaphragm and Intercostal Muscles: Contract to increase lung volume, relax to decrease it. o Inhalation: Active process; air is drawn into the lungs. o Exhalation: Passive process; air is pushed out of the lungs. o Residual Volume: Air rich in carbon dioxide remains trapped in alveoli and mixes with incoming oxygen-rich air. Cardiovascular/Circulatory System Overview: The cardiovascular system, also known as the circulatory system, is responsible for circulating blood throughout the body. This system facilitates nutrient distribution and waste removal. It includes the heart, blood vessels (arteries, veins, and capillaries), and blood. Heart Structure: o Made of cardiac muscle. o Four chambers: two atria (upper chambers) and two ventricles (lower chambers). o Right ventricle pumps blood toward the lungs o The right and left ventricles have thicker walls than the two atria. Blood Components: o Plasma: Contains nutrients, hormones, antibodies, and immune proteins. o Red Blood Cells: Contain hemoglobin for oxygen transport.  o White Blood Cells: Defend against pathogens; includes granulocytes (basophils, eosinophils, neutrophils) and agranulocytes (monocytes, lymphocytes). o Platelets: Responsible for blood clotting. Blood Circulation: o Closed Circulatory System: Blood is pumped by the heart through a network of arteries, veins, and capillaries. o Pulmonary Loop: Carries deoxygenated blood from the right ventricle to the lungs for oxygenation and returns oxygenated blood to the left atrium. o Systemic Loop: Carries oxygenated blood from the left ventricle to the body and returns deoxygenated blood to the right atrium. Systole and Diastole: o Systole: Contraction of heart muscles. o Diastole: Relaxation of heart muscles. Immune System Barriers Overview: The immune system uses barriers to prevent pathogens from entering the body. These barriers are the first line of defense, preventing infections and maintaining overall health. When pathogens breach these barriers, internal defenses are activated. External Barriers: o Prevent pathogens from entering the body. o Includes physical and chemical barriers. Internal Barriers: o Activated when external barriers are breached. o Include inflammatory responses and defensive cells/chemicals that attack pathogens. Physical Barriers:  o Skin: A primary physical barrier. o Mucus: Traps pathogens. Chemical Barriers: o Low pH: Inhibits pathogen growth. o Salt: Creates a hypertonic environment. o Enzymes: Break down pathogens. o Secretions: Such as acid, enzymes, and salt that prevent pathogen entry. Commensal Microorganisms: o Microscopic organisms that live on the human body without causing harm. o They create a cellular barrier. Immune Responses Overview: The immune system protects the body from disease-causing agents (pathogens) through innate and adaptive defenses. The innate immune system provides nonspecific, immediate responses, while the adaptive immune system mounts specific responses and remembers pathogens. Key components include physical barriers, cells, and chemical signals. Innate Immune System: o Nonspecific defense mechanisms present from birth. o Includes: ▪ Physical barriers: Skin, mucus membranes. ▪ Chemical barriers: Low pH, salt, enzymes, antimicrobial peptides. ▪ Internal defenses: Phagocytes, natural killer (NK) cells, interferons, complement system. Adaptive Immune System: o Specific response to pathogens, develops over time. o Involves lymphocytes (T cells and B cells).  o Two types of responses: ▪ Cellular (cell-mediated) response: Destroys infected cells. ▪ Humoral (antibody-mediated) response: Destroys pathogens in body fluids using antibodies. Inflammatory Response: o Innate immune response triggered by tissue injury or infection. o Involves release of histamine, increasing blood flow and attracting phagocytes. o Can cause fever to speed up the immune response. Cellular Response: o Part of the adaptive immune system, mediated by T cells. o Targets and destroys infected cells. Humoral Response: o Part of the adaptive immune system, mediated by B cells. o Produces antibodies to neutralize pathogens in body fluids. T Cells: o Lymphocytes that mature in the thymus. o Key players in cellular immunity. B Cells: o Lymphocytes that mature in the bone marrow. o Produce antibodies in humoral immunity. Antigen-Presenting Cells (APCs): o Cells that digest pathogens and present antigens to T cells. o Examples: Macrophages. o Activate helper T cells.