BIOD 151(Fall 2021) M1 Notes and EXAM BioD151 Lab 1 - Key Terms Module 1

BIOD 151(Fall 2021) M1 Notes and EXAM BioD151 Lab 1 - Key Terms Module 1 1.1 overview of physiology and major systems Anatomy and physiology are studies of how the human body works. Anatomy focuses on the structure of the body and how it is designed, and physiology looks at how the body functions. The physiology of the body depends on the anatomy of the body. The physiology of how the organs function depends on the structure of the bones, which are hard structures made of mineral deposits that protect the organs from damage. It is important to study anatomy and physiology together because they are so closely related. The human body has many levels of organization (Figure 1.1). Studying the human body at the chemical level is to look at atoms, which are the smallest building blocks of matter. Atoms combine to form molecules, which then combine to form macromolecules (such as proteins and nucleic acids). Macromolecules combine to form organelles (working structures) inside of each human cell. Examples of organelles are the nucleus and mitochondria of the cell. The cells are the smallest units of living organisms and comprise the cellular level of structural organization. There are many different types of cells in the body that perform various functions; together, they form the tissue level. Figure 1.1 Levels of organization in the human body Tissues are groups of cells that perform a common function. The four basic tissue types in the human body are epithelium, muscle, connective, and nervous tissue, each of which is made up of specific cell types that perform specific functions. Epithelial tissue (Figure 1.2) covers the body surface and lines the cavities of the body. The cells that make up epithelial tissue are specialized for tasks such as secretion and absorption. The structure of epithelial tissue contains closely packed cells with very little matrix (layer outside the cells). Epithelial tissue can be found as one layer or in many layers. These cells are under constant cell division to replace dead cells that shed away. Figure 1.2 Epithelial tissue lining the cavities inside the body shown in pink Muscle tissue enables us to move (Figure 1.3). The cells that make up muscle tissue are specialized for muscle contraction. Figure 1.3 Anterior view multiple layers of muscular tissue (visible in context with skeleton, internal organs, arteries, and veins) Connective tissue (Figure 1.4) offers support and protection of body organs and includes bones, tendons, blood, and ligaments. Connective tissue cells are specialized to bind tissues together and play a supportive role. Figure 1.4 View various types of connective tissue in context (bones, blood, tendons, ligaments) Nervous tissue (Figure 1.5) is responsible for the communication between the cells of the body by forming a system of electrical impulses that communicate very rapidly. Nerves are like the “wiring” of the body. Figure 1.5 Nervous tissue (nerves) in yellow Together the tissues make up the organ structure level of the body (Figure 1.1). The organs of the body perform very specific functions. Examples of organs that we will study are the liver, brain, lungs, heart, and kidneys. Organs carry on extremely complex functions. Organs will work together to accomplish necessary functions. An example of this is how the heart and the blood vessels that make up the cardiovascular system circulate blood continuously to carry oxygen and nutrients to all the cells that make up the body.