Chapter 4 - Body Organization And Homeostasis Flashcards
Epithelial shapes
Squamous: flattened, scale like
- thin cells allow for efficient diffusion
- smooth surface reduces friction
Cuboidal
- provide some protection
- involved in secretion and/or absorption
Columnar
-absorption and secretion
Epithelial structure
Free membrane for protection, secretion, absorption
Basement membrane is cell-free; attaches free membrane to tissues below
Connective tissue functions
Bind tissues
Support (cartilage, bone)
Transport (blood)
Energy storage (adipose tissue)
Connective tissue structure
Cells within extra cellular matrix
Matrix of protein fibers and ground substances
Fiber
- collagen: strong, resist stretching
- elastic
- reticular : branching strands of collagen for support
3 types of Muscle tissues
Skeletal
Cardiac
Smooth
Skeletal muscle tissue function
Has striated cells with multiple nuclei
Occurs in muscles attached to skeleton
Functions in voluntary movement of body
Smooth muscle function
Has spindle- shaped cells, each with a single nucleus
Cells have no striations
Functions in movement of substances in lumens of body
Is involuntary
Is found in blood vessel walls and walls if digestive tract
Cardiac muscle
Has branching, striated cells, each work a single nucleus
Occurs in the wall of the heart
Functions in the pumping of blood
Is involuntary
Skin functions
Protect from pathogens, chemicals, and physic factors
Prevents water loss
Regulates temperature - through sweating
Synthesis of vitamin d
Detecting stimuli: touch, heat, pain
Skin structures
Epidermis and dermis
Epidermis structure
Outermost layer; thin
Cells are flat, dry, and dead
Filled with protein keratin that resists bacteria and fungi
Lose 35,000 cells per minute
Replaced by dividing cells from dermis
Site for lipid-soluble drug delivery
Dermis structure
Inner layer; much thicker
Contains blood vessels for nourishments (lacking in epidermis)
Contains sensory receptors, oil glands, nerve fibers, sweat glands; hairs/hair follicles
Lower layer with connective tissue: collagen and elastic fibers, so skin stretches. Which declines with age
What factors promote skin cancer
Too much ultra violet radiation
Basal cell carcinoma
Derived from stem cells gone awry, is the more common type of skin cancer and is the most curable
Melanoma
Type if skin cancer deceived from melanocytes, is extremely serious
Homeostasis
Is the body’s ability to maintain a relative constancy of its internal environment by adjusting its physiological processes.
Give an example of homeostasis
The ability of the body to regulate the acid-base balance of the body. Co2 enters blood, it combines with water to create carbonic acid. However, blood is buffered - pH stays within normal range as long as the lungs are busy excreting carbon dioxide. Kidneys backs up the two mechanism, which gets rid of wide range of acidic and basic substances, and therefore, adjust the pH
Exocrine gland
Glands with ducts that secrete their product onto the outer surface or into a cavity
Endocrine gland
Secrete hormones directly into the bloodstream
Fribroblasts
Loose fibrous and dense fibrous connective tissues cells located some distance from one another and separated by a jellyfish like ground substance containing white collagen fibers and yellow elastic fibers
Adipose tissue
Is a special type of loose connective tissue in which the cells enlarge and store fat.
