Primary Tissues Flashcards
What are the three main divisions of cells?
the single celled organisms (known as the prokaryotes and eukaryotes)
the simple multicellular organisms (sponges and hydra etc.)
complex multicellular organisms (higher animals/plants) these cells group together into tissues with distinct functions.
What is an originator cell
a stem cell
What is gene expression regulated by?
transcription factors as they act in different combinations to determine the path of differentiation.
What is Epithelia
Thery are used for absorption secretion transport protection they cover surfaces with sheets of cells creating an enclosed and sheltered environment
What happens when a burn occurs?
this causes loss of skin barrier function and the main dangers are fluid loss and infection.
Gap junctions
connect cytosols of adjacent cells for very small molecules
What does the basement membrane contain that provides strength
filamentous proteins
What are fibro - collagenous tissue
These can be loose (around epithelial/organs type 1 collagen, cells ++) dense (tendon, ligaments type 1 collagen cells+/-) or reticular (liver, lymph nodes type 111 collagen).
Fibroblasts
synthesise fibrous proteins such as collagens, elastin’s and extracellular matrix components proteoglycans
Macrophages
phagocytose foreign bodies/organisms. Present antigens to stimulate immune cells
Mast cells
synthesise histamine and other mediators of inflammation
Plasma cells
synthesise antibodies (mature B cells)
adipocytes
fat cells
adipose tissue (white fat)
White fat = energy store, insulation and protection
Brown fat =
heat protection by uncoupling oxidative phosphorylation in mitochondria, located near the upper trunk region.
What does blood contain
Fibrous proteins
Structural carbohydrates and proteins
Mineral deposits
What is muscle?
contractile tissues under voluntary or involuntary, all contractile filaments are composed of actin and myosin. Ordered arrays of filaments in 2 types produce a striated appearance.
What are the three types of muscles
Skeletal muscle
Cardiac muscle
Smooth muscle
Smooth muscle
non striated, produces coordinated contractions that are involuntary, the cells are spindle shaped but cells borders are seen very clearly (there is no striking ordered arrays of myosin and actin and this is responsible for peristalsis in the gut.
What do adipocytes produce
adipokines = regulate nutrional balance
hormone produced to tell us when we are full
leptin
