Human Body Tissues, Organs, and Systems PDF

Introduction to Biology BIO 101 Human body Tissue, Organ and Glands Lecture 05 Level of organization  Tissue o Group of cells having similar structure o Perform specialized activity o Usually found together o Held together by extrac...

Introduction to Biology BIO 101 Human body Tissue, Organ and Glands Lecture 05 Level of organization  Tissue o Group of cells having similar structure o Perform specialized activity o Usually found together o Held together by extracellular fluid and fibers More than 200 cell types make up four major tissues of the body. 1. Epithelial tissue 2. Connective tissue 3. Muscle tissue 4. Nervous tissue Epithelial Tissue Consists of tightly packed cells arranged in a continuous sheet with one or more layers, and this lets them act as barriers to the movement of fluids and potentially harmful microbes Covers the surface of organs Lines cavities and canals Forms tubes and ducts Provides the secreting portions of glands Makes up the epidermis of the skin Epithelial cells are polarized e.g.  Skin  Internal covering of GIT Connective Tissue Made up of diverse cell types including fibroblasts, fat cell and blood Supports and connects other tissues and organs Muscle Tissue Essential for keeping the body upright, Contain contractile protein myosin and actin allowing it to move, and even pumping blood filaments and pushing food through the digestive tract E.g. Muscle cells, often called muscle fibers  Skeletal(Voluntary) Cells that are able to contract  Smooth(involuntary)  Cardiac(heart) Nervous Tissue Highly specialized tissue involved in sensing stimuli—external or internal cues—and processing and transmitting information Allows to move, Think, Taste See Experience all functions associated with being alive consists of two main types of cells: neurons, or nerve cells, and glia  neurons are the basic functional unit of the nervous system  glia mainly act to support neuronal function.  Organ Collection of tissues united together to perform a particular function E.g.  Stomach is one organ found within the digestive system consisting of tissues responsible for the storage and digestion of food Animal organ Main tissues Functions Heart Muscle, nerve and Muscular pump for blood blood circulation Brain Blood, nerve Detection, processing and transmission of information Liver Connective, blood Metabolism of waste material, production of bile and urea and storage of glycogen Plant organ Main tissues Functions Root Epidermal and Absorption of water and vascular nutrients Stem Epidermal, vascular Transport of materials to and and parenchyma from roots Leaf Epidermal, mesophyll Production of carbs by and vascular photosynthesis  Organ Most organs contain all four tissue types The inside of the intestine is lined by epithelial cells Around the epithelial layer are layers of connective tissue and smooth muscle, interspersed with glands, blood vessels, and neurons smooth muscle contracts to move food through the gut, under the control of its associated networks of neurons Organ Systems Organs are grouped into organ systems, They work together to carry out a particular function for the organism  The heart and the blood vessels make up the cardiovascular system  Work together to circulate the blood, bringing oxygen and nutrients to cells throughout the body and carrying away carbon dioxide and metabolic wastes Organ Systems  The respiratory system includes the nose, mouth, pharynx, larynx, trachea, and lungs  Brings oxygen into the body and gets rid of carbon dioxide. Major organ systems of the human body Major organ systems of the human body Major organ systems of the human body Major organ systems of the human body Major organ systems of the human body Organs in a system work together Organ system must work together for the system to function as a whole The mouth, stomach, small intestine, and other digestive system organs work together to make digesting food and absorbing nutrients efficient Digestion wouldn’t work well if your stomach stopped churning or if one of your enzyme-producing glands—like the pancreas—decided to take the day off!  Organ systems work together as well Different organ systems also cooperate to keep the body running For example, the respiratory system and the circulatory system work closely together to deliver oxygen to cells and to get rid of the carbon dioxide the cells produce The circulatory system picks up oxygen in the lungs and drops it off in the tissues, then performs the reverse service for carbon dioxide The lungs expel the carbon dioxide and bring in new oxygen-containing air Only when both systems are working together can oxygen and carbon dioxide be successfully exchanged between cells and the environment  The blood in your circulatory system has to receive nutrients from your digestive system and undergo filtration in your kidneys, or it wouldn't be able to sustain the cells of your body and remove the wastes they produce  Control and Coordination Many body functions are controlled by The nervous system uses electrical the nervous system and the endocrine impulses to collect, process, and respond system to information about the environment Use chemical messengers to affect the The endocrine system produces and uses function of the other organ systems and chemical signals called hormones, to coordinate activity at different which travel through the bloodstream locations in the body and control the actions of cells and organs Gland Glands are organs They produce and release substances that perform certain functions Located throughout the body Fall into two types:  Endocrine and  Exocrine Endocrine glands Examples of glands  adrenal glands part of your endocrine system  pituitary gland make hormones and release them  hypothalamus into the bloodstream  thyroid control a number of important functions in your body, such as: There are also organs that contain endocrine tissue and act as glands.  growth and development These include the:  metabolism   pancreas mood   kidneys reproduction  ovaries  testes  Exocrine glands Produce other substances — not Examples of glands hormones  salivary Released through ducts to the exterior of  sweat your body  mammary  sebaceous  regulate your body temperature,  protect your skin and eyes, and  lacrimal  mothers feed babies by producing breast milk. Common Glands and Hormones Common Glands and Hormones  Who regulates THE REGULATORS? The endocrine system is regulated by negative feedback mechanisms that work to maintain homeostasis. For example, blood glucose regulation Thank You