Essay about Structure And Function Of Cells And Tissues N Blood

Submitted By munti7
Words: 5318
Pages: 22

Anotomy is the science of structure and the relationships revealed by dssection and histology.
Physiology is the science of the normal body functions.
There are many subdiviasions in anatomy n phyisi.
Anatomy helps locate rgions within the whole body, organs n tissues, also for diagnosis.
The anatomical position are: proximal= top length vertical, distal= bottom half vertical, midline= middle vertical, lateral= above neck horizontal, medial= bottom half, superor= top, inferior= bottom, dorsal=posterior back, ventral= anterior front.
Planes are imaginary flat sufaces that divide the body/organs into areas; saggittal= left and right division, midsagittal=equal, parasagittal=unequal, oblique= diagnol division, frontal/coronal= front and back division, transverse= inferior superior division, mid saggital= mid . organ sections are flat surfaces resulting from cuts through body structures.
Need to know where to section as enables specimens to be correctly diagnosed or researched, n appearnce depends on where you slice it.
Tissue sections: longitudinal section= tissue cut along longest diresction of organ, oblique= tissue cut at angle, transverse/cross section= tissue cut perpendicular to length of organ,
Body organisation n physiology
6 levels of structural organisations: chemical-cellular-tissue-organ-system-organismal. Lvl 1=biochemical n molecular, lvl 2=cells: cytology is the study of cell structure, a cell is a basic living functional unit of the body, cell physiology is the study of cell function. The cells vary considerbly: 100 trillion cells in the body n over 200 diff types whch vary in mrphology n function. Lvl 3=tissues: gps of similar cells r called tissues, 4 basic types originating from primary germ layers in the embryo: connective is most abundant for support n protection, epithelial forms flat sheets, nervous is neurones conducting electrical impulses controlling body functions, muscle consists of skeletal muscle for locomotion n posture, smooth muscle forms walls of tubular structures and thirdly the cardiac muscle. Lvl 4= organ: gps of two or more tissue types into a structure with a specific function. Gp5= system : collection of related organs with a common function. Lvl 5=one living individual.
11 body systems are MIND CURLERS stands for: Muscular,Integumentary(skin,hair),Nervous, Digestive, Cardiovascular, Urinary, Reproductive, Lymphatic and immune, Endocrine, Respiratory, Skeletal.
Physiology. In vivo= study within living organism. In vitro=study in the test tube. Body maintains a stable internal enviro through homeostasis. Cells are influenced by many internal n external factors.
Homeostasis can be positive or negative.
Lab investigations histology is study of tissues. Cytology is study of cells both essential for understanding n diagnosing disease.
3 main types of microscope: light, TEM/SEM, flourescent. For the light microscope: magnigfication= eyepiece*objective, steps include: tissue fixation,tissue embedding, tissue sectioning, furthr processing like dewaxing, mounting n visualisation. To further increase visualisation histological stains are used for greater clarifications, and, immunohistochemistry uses antibodies to stain fine detail.
The flourescent microscope has sme magnification as light microscope, but, uses flourescent dyes to visualise structurs and functions, laser scanning confocal microscopes can look at 3d tisssue. The basis of this is uv lamp or laser- excitation- emission from filter- detection.
Electron microscope= greatest magnification, fires a specimen with an electron beam n measures the voltage of electrons given off to form an image, has higher resolution.
Connective tissue- structure
Four types of tissue: muscle-for body movement n specialised for contaction , nervous-transmits messages n electrical , epithelial-protection n secretion+absorption , connective-supports coneects n seperates tissues n organs.
Connective tissue:provides structural n metabolic support for other