FOHA111 WEEK 2.pdf - FOHA111 PRELIMS 2021 LECTURE / BSPT...

FOHA111
PRELIMS 2021
LECTURE / BSPT 1-A-2
CELL PARTS AND FUNCTIONS
CELL
NUCLEUS
• a large organelle that houses most of a cell’s DNA. Within
the nucleus, each chromosome, a single molecule of DNA
associated with several proteins, contains thousands of
hereditary units called genes that control most aspects of
cellular structure and function.
o NUCLEOLUS
o NUCLEAR ENVELOPE
o CHROMATIN
ENDOPLASMIC RETICULUM (ER)
• SMOOTH ER
o Unlike rough ER, smooth ER does not have
ribosomes on the outer surfaces of its membrane.
o contains unique enzymes, because it lacks
ribosomes, smooth ER does not synthesize
proteins, but it does synthesize fatty acids and
steroids, such as estrogens and testosterone.
PRELIMINARY EXAMINATIONS
OUTLINE
I. Cell Parts & Function
o Organelles
II. Histology
o Cell Junctions
o Epithelial Tissue
o Connective Tissues
o Muscular Tissue
o Nervous Tissue
III. Components of the Integumentary System

• ROUGH ER
o Proteins synthesized by ribosomes attached to
rough ER enter spaces within the ER for processing
and sorting. In some cases, enzymes attach the
proteins to carbohydrates to form glycoproteins.
• RIBOSOMES
o large and small subunits are made separately in the
nucleolus, a spherical body inside the nucleus. Once
produced, the large and small subunits exit the
nucleus separately, then come together in the
cytoplasm.
GOLGI APPARATUS
• CISTERNAE
o often curved, giving the Golgi complex a cuplike
shape. Most cells have several Golgi complexes,
and Golgi complexes are more extensive in cells that
secrete proteins, a clue to the organelle’s role in the
cell.
• SECRETORY VESICLES
o deliver the proteins to the plasma membrane, where
they are discharged by exocytosis into the
extracellular fluid.
o i.e., certain pancreatic cells release the hormone
insulin in this way.
• TRANSPORT VESICLE
o move specific enzymes back toward the entry face
and move some partially modified proteins toward
the exit face.
• Materials are transported from the Rough ER to Golgi to the
cell membrane by vesicles.
• Entry (cis) face accepts proteins from rough ER; medial
cisternae form glycoproteins, glycolipids, and lipoproteins;
exit (trans) face modifies molecules further, then sorts and
packages them for transport to their destinations.
LYSOSOME
• contain as many as 60 kinds of powerful digestive and
hydrolytic enzymes that can break down a wide variety of
molecules once lysosomes fuse with vesicles formed during
endocytosis.
• Vesicle formed from Golgi complex; contains digestive
enzymes.
• HYDROLASE ENZYME
• PINOCYTOSIS VS. PHAGOCYTOSIS
PEROXISOME
• Peroxisomes, also called microbodies, contain several
oxidases (oxidative enzymes), enzymes that can oxidize
(remove hydrogen atoms from) various organic substances.
For instance, amino acids and fatty acids are oxidized in
peroxisomes as part of normal metabolism.