HUMAN ANATOMY AND PHYSIOLOGY
LESSON 3: CELLS AND TISSSUE
I. Anatomy of a Generalized Cell
3 Main Regions
1. Nucleus
DNA - a blueprint that contains all the
instructions needed for building the
whole body.
2. Plasma membrane
o Necessary for cell reproduction.
The Fluid Mosaic Model - structure of
o Composed of genes – carry the
the plasma membrane consists of two
instructions for building proteins.
phospholipid (fat) layers arranged “tail to
o A cell that has lost or ejected its
tail,” with cholesterol and floating
nucleus is destined to “self-
proteins scattered among them.
destruct”.
Polar heads of phospholipid molecules
3 Regions or Structures
are hydrophilic.
a. nuclear envelope- allows some but not
Nonpolar fatty acid tails are hydrophobic.
all substances to pass through it, but
The hydrophobic makeup of the
substances pass through it much more
membrane interior makes the plasma
freely than elsewhere because of its
membrane relatively impermeable to
relatively large pores.
most water-soluble molecules.
nucleoplasm- jellylike fluid where
Cholesterol - helps to both stabilize the
other nuclear elements are
membrane and keep it flexible.
suspended.
Proteins scattered - responsible for most
b. nucleolus – sites where ribosomes are
of the specialized functions of the
assembled.
membrane.
c. chromatin – beads on a string
chromosomes- when chromatin coil
and condense to form dense chromo Proteins Function
(colored) and soma (body)
carrier proteins Bind to a substance
and move it
through the
membrane.
glycoproteins “Sugar-protein”
determine your
blood type; act as
receptors that
certain virus,
bacteria and toxins
can bind to.
Psalms 119:50
, HUMAN ANATOMY AND PHYSIOLOGY
Consists of a double membrane equal to
glycocalyx “Sugar coat” that 2 plasma membranes.
play a role in cell-to- Site of aerobic respiration and ATP
cell recognition and
synthesis.
interactions.
Outer membrane- smooth and
Cell membrane junctions featureless.
o Cells are bound in three ways: Inner membrane – has cristae – shelflike
Glycoproteins in the glycocalyx act protrusions (bulge).
as an adhesive or cellular glue. ATP - provides the energy for all cellular
Wavy contours of the membranes of work.
adjacent cells fit together in a Supply most of the ATP making them the
tongue-and-groove fashion. powerhouses of the cell.
Cell membrane junctions Liver and muscle cells – “busy cells” use
o 3 Main Types of Junctions huge amounts of ATP.
(1) Tight junctions - impermeable B. Ribosomes
junctions where adjacent plasma Made of proteins and rRNA (ribosomal
membranes fuse together tightly RNA).
like a zipper and prevent Sites of protein synthesis.
substances from passing. (e.g. C. Endoplasmic Reticulum
small intestine) It serves as a mini circulatory system for
(2) Desmosomes – anchoring the cell because it provides a network of
junctions where they prevent cells channels for carrying substances
subjected to mechanical stress (primarily protein).
(such as heart muscle cells and skin Rough ER – studded with ribosomes and
cells) from being pulled apart. The all of the building materials of cellular
“guy wires”. membranes are formed in it or on it.
(3) Gap junctions – communicating o Cell’s membrane factory.
junctions. (e.g. heart and between o Transport vesicles carry substances
embryonic cells) around the cell.
3. Cytoplasm o Abundant in cells that make
3 Major Components (synthesize) and export (secrete)
(1) Cytosol - semitransparent fluid that proteins.
suspends the other elements. More o Example: Pancreatic cells produce
water. enzymes to be delivered to the small
(2) Inclusions - are stored nutrients or intestines.
cell products floating in the cytosol. A Smooth ER - site of lipid and steroid
cellular “pantry” where items are (cholesterol) synthesis and detoxification
kept on hand until needed. of drugs and pesticides.
(3) Organelles – specialized cellular o Liver cells are chock-full of smooth
compartments. ER.
A. Mitochondria D. Golgi apparatus
“Traffic director” for cellular proteins.
Psalms 119:50
LESSON 3: CELLS AND TISSSUE
I. Anatomy of a Generalized Cell
3 Main Regions
1. Nucleus
DNA - a blueprint that contains all the
instructions needed for building the
whole body.
2. Plasma membrane
o Necessary for cell reproduction.
The Fluid Mosaic Model - structure of
o Composed of genes – carry the
the plasma membrane consists of two
instructions for building proteins.
phospholipid (fat) layers arranged “tail to
o A cell that has lost or ejected its
tail,” with cholesterol and floating
nucleus is destined to “self-
proteins scattered among them.
destruct”.
Polar heads of phospholipid molecules
3 Regions or Structures
are hydrophilic.
a. nuclear envelope- allows some but not
Nonpolar fatty acid tails are hydrophobic.
all substances to pass through it, but
The hydrophobic makeup of the
substances pass through it much more
membrane interior makes the plasma
freely than elsewhere because of its
membrane relatively impermeable to
relatively large pores.
most water-soluble molecules.
nucleoplasm- jellylike fluid where
Cholesterol - helps to both stabilize the
other nuclear elements are
membrane and keep it flexible.
suspended.
Proteins scattered - responsible for most
b. nucleolus – sites where ribosomes are
of the specialized functions of the
assembled.
membrane.
c. chromatin – beads on a string
chromosomes- when chromatin coil
and condense to form dense chromo Proteins Function
(colored) and soma (body)
carrier proteins Bind to a substance
and move it
through the
membrane.
glycoproteins “Sugar-protein”
determine your
blood type; act as
receptors that
certain virus,
bacteria and toxins
can bind to.
Psalms 119:50
, HUMAN ANATOMY AND PHYSIOLOGY
Consists of a double membrane equal to
glycocalyx “Sugar coat” that 2 plasma membranes.
play a role in cell-to- Site of aerobic respiration and ATP
cell recognition and
synthesis.
interactions.
Outer membrane- smooth and
Cell membrane junctions featureless.
o Cells are bound in three ways: Inner membrane – has cristae – shelflike
Glycoproteins in the glycocalyx act protrusions (bulge).
as an adhesive or cellular glue. ATP - provides the energy for all cellular
Wavy contours of the membranes of work.
adjacent cells fit together in a Supply most of the ATP making them the
tongue-and-groove fashion. powerhouses of the cell.
Cell membrane junctions Liver and muscle cells – “busy cells” use
o 3 Main Types of Junctions huge amounts of ATP.
(1) Tight junctions - impermeable B. Ribosomes
junctions where adjacent plasma Made of proteins and rRNA (ribosomal
membranes fuse together tightly RNA).
like a zipper and prevent Sites of protein synthesis.
substances from passing. (e.g. C. Endoplasmic Reticulum
small intestine) It serves as a mini circulatory system for
(2) Desmosomes – anchoring the cell because it provides a network of
junctions where they prevent cells channels for carrying substances
subjected to mechanical stress (primarily protein).
(such as heart muscle cells and skin Rough ER – studded with ribosomes and
cells) from being pulled apart. The all of the building materials of cellular
“guy wires”. membranes are formed in it or on it.
(3) Gap junctions – communicating o Cell’s membrane factory.
junctions. (e.g. heart and between o Transport vesicles carry substances
embryonic cells) around the cell.
3. Cytoplasm o Abundant in cells that make
3 Major Components (synthesize) and export (secrete)
(1) Cytosol - semitransparent fluid that proteins.
suspends the other elements. More o Example: Pancreatic cells produce
water. enzymes to be delivered to the small
(2) Inclusions - are stored nutrients or intestines.
cell products floating in the cytosol. A Smooth ER - site of lipid and steroid
cellular “pantry” where items are (cholesterol) synthesis and detoxification
kept on hand until needed. of drugs and pesticides.
(3) Organelles – specialized cellular o Liver cells are chock-full of smooth
compartments. ER.
A. Mitochondria D. Golgi apparatus
“Traffic director” for cellular proteins.
Psalms 119:50
