Unit 1.1 Tissues and Body Organization Flashcards
Define anatomy and physiology
Anatomy is the study of body structure; physiology is the study of body function.
Describe cells – role in structure and function of tissue, number of cells in body, and number of types of cells.
Fundamental units of structure & function
Perform basic life processes and specialized functions
Body has approx 37 trillion
Up to 200 different types
Define tissues
A group of cells that are similar in structure and function and work together to form organs and to perform tasks within the body
What are the 7 tiers of the hierarchy of organization?
atoms, molecules, cells, tissues, organs, organ systems, organism
Define organs and organ systems
Structures composed of two or more types of tissues working together.
Groups of organs working together to perform complex functions
What are the 4 types of tissue and their functions?
Epithelial – cover and protect
Connective – provides support
Muscle – movement
Nervous – control and communication
Describe 5 variations in human cells (2 pairs of opposites +1) and give examples
Some unattached (e.g., blood cells)
Some attached (e.g., epithelial cells in the trachea)
Some divide readily (e.g., skin, bone)
Some divide only under exceptional circumstances (e.g., certain nerve cells)
many are specialized to produce and secrete particular substances (e.g., pancreatic cells –> insulin, cells in bronchial passage –> mucus
Name 4 types of bone cells and describe.
osteogenic bone cells – undifferentiated stem cells; form osteoblasts
osteoblasts – immature cells; responsible for bone growth and uptake of minerals from the blood
osteocytes – star-shaped mature bone cells; regulate mineral homeostasis; majority of cells in bone tissue
osteoclasts – very large, multinucleated cells; break down bone by dissolving minerals in bone matrix and releasing them back into the blood; important for bone remodeling
What are the 5 types of white blood cells and their characteristics
neutrophils – destroy single-celled bacteria and fungi in blood; about 62% of leukocytes
lymphocytes – B cells produce antibodies; T cells destroy infected and cancerous cells; about 30%
monocytes – engulf and destroy pathogens; about 5%
eosinophils – attack larger parasites; trigger allergic reactions; about 2%
basophils – release histamine; <1%
What are the 3 shapes and the 4 layering that identify epithelial tissue?
squamous, cuboidal, columnar
simple, stratified, pseudostratified, transitional
Name the 3 types of connective tissues, the cells that create their matrices, and the composition of their matrices.
fibrous – flexible matrix; fibroblasts create the proteins collagen, elastin, and sometimes reticular fibers in the matrix
supportive – solid matrix; chondrocytes in cartilage; osteocytes in bone; composed of collagen fibers embedded in calcium phosphate
fluid – matrix is fluid; cells inside the matrix do not produce The matrix; blood contains erythrocytes, leukocytes, and thrombocytes suspended in plasma; lymph contains lymphocytes
Name 3 types of muscular tissue and describe their characteristics.
skeletal – found in muscles attached to skeleton; long cells called fibres; striated; multinucleated; voluntary movement; fast rate of contraction
smooth – found in blood vessels and walls of digestive tract; involved in peristalsis; spindle-shaped; mononucleated; no striations; involuntary movement; slow rate of contracting
cardiac – found only in wall of heart; striated; branched; involuntary; fast contractions; cells join end to end at intercalated discs
Name 2 types of nervous tissue and their roles in system.
Neurons – carry out the functions of system
Neuroglia (glial cells) – support neurons by providing nutrients, removing waste, and forming myelin sheath
What is the purpose of cell-to-cell junctions?
Hold cells and tissues together
Control movement of materials between cells
Name the three types of cell-to-cell junctions and describe their structure and purpose.
Tight junction – adjacent membranes adhere the membranes together; form a barrier, prevent leaks
Gap junction – plasma membrane channels join; allows communications and materials transfer; important for heart and smooth muscles because they allow flow of ions so cells function as unit
Adhesion junction – adjacent plasma membranes held together by protein filaments (adherens junctions and desmosomes); filaments are attached to cytoskeletons in each cell; gives strength/resists tearing; found in stomach and bladder
What two organ systems facilitate the working together of organs and organ systems?
Nervous system controls body activities
Endocrine system secretes hormones to regulate activities
Name 3 functions of organs and organ systems.
Supply body cells with necessary substances
Eliminate wastes
Maintain temperature, pH, and other conditions for life
How can different cell types arise from genetically identical cells?
Differential regulation of genes cause differential gene expression
Define histology
The study of the microscopic structure of tissues
Describe the relationship of cells to tissue in the context of the formation of tissue.
Groups of connected cells form tissues.
Cells in tissue may be of the same type or different types.
The cells work together to perform specific functions and are specialized for these functions.
The different types of cells can create all the types of tissue in the body.
Where in the body do you find epithelial tissue?
Lines inner and outer body surfaces (e.g., skin, digestive tract)
What are the functions of epithelial tissue?
Protection
Secretion (e.g., hormones)
Absorption (e.g., nutrients)
How do the shape and layering affect the functioning of epithelial tissue?
Thin shape facilitates diffusion/absorption
Large cells support secretion/protection
What are the key identifying features of epithelial tissue?
Free surface – not attached to other cells; are exposed to outside or inside of hollow organs/tubes
Basement membrane – anchors epithelial tissue to underlying cells
Tissue is identified and named by shape and layering
