Lecture 4 - Material (1) 2 PDF

**https://www.youtube.com/watch?v=jOojs-pvLNo** **STRUCTURE OF THE BODY** The body is made up of increasing larger, and more complex, structural units. From smallest to largest these are: ***cells, tissues, organs***, and the ***body systems***. Working together, these structures form the complete...

**https://www.youtube.com/watch?v=jOojs-pvLNo** **STRUCTURE OF THE BODY** The body is made up of increasing larger, and more complex, structural units. From smallest to largest these are: ***cells, tissues, organs***, and the ***body systems***. Working together, these structures form the complete body and enable it to function properly. **CELLS** Cells are the basic structural and functional units of the body. Cells are specialized and grouped together to form tissues and organs. - Cytology is the study of the anatomy, physiology, pathology, and chemistry of the cell Cyt[ology] cyt means cell -ology means study of *[Terms Related to Cells ]* Anabolism- Process of building up large proteins from small protein pieces called amino acids. Catabolism- Process whereby complex nutrients are broken down to simpler substances and energyis released. Cell membrane-Structure surrounding and protecting the cell. It determines what enters and leaves the cell. Chromosomes- Rod-shaped structures in the nucleus that contain regions of DNA called genes. Cytoplasm- All the material that is outside the nucleus and yet contained within the cell membrane. DNA - Chemical found within each chromosome. Metabolism- Total of the chemical processes in a cell. It includes catabolism and anabolism. Meta- means change - bol means to cast, and -ism means a process. Introduction of human cell and its composition - YouTube **TISSUES** Tissues are groups of similar cells that perform the same role; each tissue has at least one unique function. Tissues are classified by structure and function and are divided into four types: ***epithelial***, ***connective***, ***muscle,*** and ***nervous***. - **Histology** is the study of the structure, composition, and function of tissues [Histology] hist means tissue -ology means a study of E.g.***Histology*** is used during autopsies and forensic investigations to help understand unexplained deaths. - A **histologist** is a specialist in the study of the organization of tissues at all levels (hist means tissue, and -ologist means specialist). [Histologist] hist means tissue -ology means a study of 1. Which statement supports the fact that bone cellsare smaller than bone tissues? 2. What is an organ? Give an example of an organ? 3. List two organ systems? 4. Which organ system do you think is the most interesting? Why? 5. Why is it necessary for the respiratory and circulatory systems to work together?