Theme 1: Organelles and Energy (2:13-15;
5:15-19, 22-23; 6:1-5, 8-9; 7:1-14, 17,19;
27:1-4, 9; 40:1-3)
Complex carbohydrates are made up of simple sugars.
• Carbohydrates: Molecules made up of C, H, and O atoms (usually in the
ra<o 1:2:1); Provide the principle source of energy for metabolism
• Simplest carbohydrates are sugars/saccharides
◦ Linear, or usually, cyclic molecules containing 5-6 carbon atoms
◦ All 6-C sugars have the chemical formula C6H12O6 but, differ in
configura<on
• For instance, glucose, galactose and fructose
• A condensa<on reac<on between the OH group on C-1 of one molecule
and C-4 of another monosaccharide give either the alpha 1-4 glycosidic
linkage or beta 1-4 glycosidic linkage
• A simple sugar is also known as a monosaccharide and 2 simple sugars
linked together by a covalent bond is a disaccharide (like sucrose- a
combina<on of glucose and fructose)
◦ Monosaccharide: Unbranched carbon chains with either an
aldehyde (HC=O) (making them aldoses) or a ketone (C=O) group
(making them ketoses)
• To form a ring, carbon in the aldehyde or ketone group
forms a covalent bond with the oxygen of a hydroxyl group
carried by another carbon in the molecule
• (The groups aVached to any carbon therefore project either above or
below the ring)
• Monosaccharides are aVached by covalent, glycosidic bonds (which are
formed by the loss of a water molecule)
• Nucleo<des contain a 5-C sugar, either ribose (in RNA) or deoxyribose
(in DNA)
, • Simple sugars combine in many ways to form polymers called
polysaccharides that provide long-term energy storage (starch and
glycogen) or structural support (cellulose in plant cell walls)
◦ Starch is made up of alpha 1-4 glycosidic linkages between alpha-
glucose monomers
• Unbranched amylose
• Branched amylopec<n- The branches form by glycosidic
linkages between the C-1 of one glucose molecule and C-6
of another
▪ It is o^en these starches that we consume and use as
energy in our own bodies
• Long, branched chains of monosaccharides are called complex
carbohydrates
◦ Some complex carbohydrates are composed of a single type of
monosaccharides (like starch, a sugar storage molecule in plants,
which contains only glucose) while others are a mic (like pec<n, a
component of the cell wall, with contains 5 different
monosaccharides)
5.4 The Endomembrane System
• Many of the organelles in cells communicate with each other
◦ Some are physically connected by membrane "bridges" or
communicate by the budding and fusing of vesicles(small
membrane-enclosed sacs that transport substances)
• Endomembrane System: Includes the nuclear envelope, endoplasmic
re<culum, Golgi apparatus, lysosomes, the plasma membrane and the
vesicles that move between them
• Most prokaryotes don't have extensive internal membranes but,
photosynthe<c bacteria do have internal membranes for harnessing
light energy
The endomembrane system compartmentalizes the cell.
• Molecules within the interior of the ER can stay there, end up in the
Golgi apparatus or end up outside the cell by the budding off and fusing
of a vesicles
, • Molecules associated with the ER membrane can move to the Golgi
membrane or the plasma membrane by vesicle transport
• Molecules in the cytosol are separated by the membranes of the
endomembrane system
• Recall that membranes can change their lipid and protein composi<on
over <me
• Exocytosis: Provides a way for a vesicle to empty its contents to the
extracellular space or to deliver proteins embedded in the vesicle
membrane to the plasma membrane
• Endocytosis: A vesicle can bud off from the plasma membrane, bringing
materials from outside the cell into a vesicle, which can then fuse with
other organelles
• Advantageous because:
◦ Specific sets of enzymes responsible for specific biochemical
func<ons can be kept in close proximity to each other
◦ Incompa<ble processes such as synthesis and degrada<on can be
kept separate and not interfere with each other
The nucleus houses the genome and is the site of RNA synthesis.
• Nucleus- Stores DNA, the gene<c material that encodes the informa<on
needed for all the ac<vi<es and structures of the cell
• Nuclear Envelope- Defines the boundary of the nucleus; Consists of 2
membranes, the inner and outer membranes, and each is a lipid bilayer
with associated proteins
◦ These 2 membranes are con<nuous at protein opening called
nuclear pores (which act as gateways that allow molecules to
move into and out of the nucleus
• The transfer of informa<on encoded by DNA depends on
the movement of RNA molecules out of the nucleus, while
the control of how and when this informa<on is expressed
depends on the movement of proteins into the nucleus
The endoplasmic re<culum is involved in protein and lipid synthesis.
• Outer membrane of the nuclear envelope is physically con<nuous with
the ER
5:15-19, 22-23; 6:1-5, 8-9; 7:1-14, 17,19;
27:1-4, 9; 40:1-3)
Complex carbohydrates are made up of simple sugars.
• Carbohydrates: Molecules made up of C, H, and O atoms (usually in the
ra<o 1:2:1); Provide the principle source of energy for metabolism
• Simplest carbohydrates are sugars/saccharides
◦ Linear, or usually, cyclic molecules containing 5-6 carbon atoms
◦ All 6-C sugars have the chemical formula C6H12O6 but, differ in
configura<on
• For instance, glucose, galactose and fructose
• A condensa<on reac<on between the OH group on C-1 of one molecule
and C-4 of another monosaccharide give either the alpha 1-4 glycosidic
linkage or beta 1-4 glycosidic linkage
• A simple sugar is also known as a monosaccharide and 2 simple sugars
linked together by a covalent bond is a disaccharide (like sucrose- a
combina<on of glucose and fructose)
◦ Monosaccharide: Unbranched carbon chains with either an
aldehyde (HC=O) (making them aldoses) or a ketone (C=O) group
(making them ketoses)
• To form a ring, carbon in the aldehyde or ketone group
forms a covalent bond with the oxygen of a hydroxyl group
carried by another carbon in the molecule
• (The groups aVached to any carbon therefore project either above or
below the ring)
• Monosaccharides are aVached by covalent, glycosidic bonds (which are
formed by the loss of a water molecule)
• Nucleo<des contain a 5-C sugar, either ribose (in RNA) or deoxyribose
(in DNA)
, • Simple sugars combine in many ways to form polymers called
polysaccharides that provide long-term energy storage (starch and
glycogen) or structural support (cellulose in plant cell walls)
◦ Starch is made up of alpha 1-4 glycosidic linkages between alpha-
glucose monomers
• Unbranched amylose
• Branched amylopec<n- The branches form by glycosidic
linkages between the C-1 of one glucose molecule and C-6
of another
▪ It is o^en these starches that we consume and use as
energy in our own bodies
• Long, branched chains of monosaccharides are called complex
carbohydrates
◦ Some complex carbohydrates are composed of a single type of
monosaccharides (like starch, a sugar storage molecule in plants,
which contains only glucose) while others are a mic (like pec<n, a
component of the cell wall, with contains 5 different
monosaccharides)
5.4 The Endomembrane System
• Many of the organelles in cells communicate with each other
◦ Some are physically connected by membrane "bridges" or
communicate by the budding and fusing of vesicles(small
membrane-enclosed sacs that transport substances)
• Endomembrane System: Includes the nuclear envelope, endoplasmic
re<culum, Golgi apparatus, lysosomes, the plasma membrane and the
vesicles that move between them
• Most prokaryotes don't have extensive internal membranes but,
photosynthe<c bacteria do have internal membranes for harnessing
light energy
The endomembrane system compartmentalizes the cell.
• Molecules within the interior of the ER can stay there, end up in the
Golgi apparatus or end up outside the cell by the budding off and fusing
of a vesicles
, • Molecules associated with the ER membrane can move to the Golgi
membrane or the plasma membrane by vesicle transport
• Molecules in the cytosol are separated by the membranes of the
endomembrane system
• Recall that membranes can change their lipid and protein composi<on
over <me
• Exocytosis: Provides a way for a vesicle to empty its contents to the
extracellular space or to deliver proteins embedded in the vesicle
membrane to the plasma membrane
• Endocytosis: A vesicle can bud off from the plasma membrane, bringing
materials from outside the cell into a vesicle, which can then fuse with
other organelles
• Advantageous because:
◦ Specific sets of enzymes responsible for specific biochemical
func<ons can be kept in close proximity to each other
◦ Incompa<ble processes such as synthesis and degrada<on can be
kept separate and not interfere with each other
The nucleus houses the genome and is the site of RNA synthesis.
• Nucleus- Stores DNA, the gene<c material that encodes the informa<on
needed for all the ac<vi<es and structures of the cell
• Nuclear Envelope- Defines the boundary of the nucleus; Consists of 2
membranes, the inner and outer membranes, and each is a lipid bilayer
with associated proteins
◦ These 2 membranes are con<nuous at protein opening called
nuclear pores (which act as gateways that allow molecules to
move into and out of the nucleus
• The transfer of informa<on encoded by DNA depends on
the movement of RNA molecules out of the nucleus, while
the control of how and when this informa<on is expressed
depends on the movement of proteins into the nucleus
The endoplasmic re<culum is involved in protein and lipid synthesis.
• Outer membrane of the nuclear envelope is physically con<nuous with
the ER
