Origin of Tissues
Blastocyst
A term to describe a pre-embryo
Controls permeability, catches pathogens from entering, and acts as the body’s first line of protection (wear and tear)
The functions of epithelial tissue
True or false: Blood and lymph are not connective tissues because it is considered as an organ as it contains specialized cells that perform specific functions like transporting nutrients and oxygen throughout the body
False: they are fluid connective tissues. Their cells circulate in a liquid extracellular matrix
Define: Muscle tissue
Excitable - responds to electrochemical stimulation and contracts the provide movement
Result of identical twins
Pre-embryo splits into two
Tight junctions, anchoring junctions, and gap junctions
Epithelial cell junctions
Cells, large ground substance, and protein fibers
Three characteristic components of connective tissues
Define: Nervous tissue
Forms the brain, spinal chord, and nerves
Excitable - integral to the propagation of electrochemical signals in the form of nerve impulses that communicate between different regions of the body
Germ layers
Ectoderm, Mesoderm, Endoderm
(simple & stratified) squamous, cuboidal, columnar (pseudostratified)
Types of epithelial tissue
Connective tissue proper, supportive connective tissue, fluid connective tissue
Classification of connective tissue
Skeletal (voluntary) muscle, smooth muscle (mostly involuntary), and cardiac muscle
3 major types of muscle tissue
Gives rise to the epidermis and nervous tissue
Ectoderm
Found in only the urinary system
When bladder is empty, the epithelium is convoluted
As bladder fills with urine, epithelium loses its convolutions and its apical cells turn from cuboidal to squamous
Transitional epithelium
Define how bone and cartilage are supportive connective tissues
Bone: hardest connective tissue, supports the body, provides a framework for skeletal muscles, provides protection to internal organs
Cartliage: important role in joint function and embryonic development
Gives rise to muscle and bone
Mesoderm
Mesocrine secretion, apocrine secretion, holocrine secretion
Exocrine glands
Found between many organs
Acts to absorb shock and bind tissues together
Allows water, salts, and various nutrients to diffuse through adjacent or embedded cells and tissues
Involves: adipose tissue, areolar tissue, reticular tissue
Loose connective tissue