LESSON 3: PLANT CELLS EUKARYOTIC CELLS PROKARYOTIC CELLS
PHBIOSC 201 – LEC
- Derived from Greek eu or - Derived from the
Ms. Rody Rica Agdipa
“true” and kary “nucleus”. Greek pro or “before”
- Generally larger and have and kary or “nucleus”.
PLANT CELLS more complex structures. - Genetically smaller
- Genetic material is and simpler.
located in the nucleus, - A cell that lacks the
Coconut tree (Cocos nusifera)
which is bounded by a nucleus and other
• Composed of: (1) a delicate base that anchors it to
membrane. membrane-bounded
a rock or piece of coral (2) long slender stalk (3) cap
- The cytoplasm also organelles.
• Different species of mermaid’s wineglass have caps contains membrane-bound
with different shapes organelles.
• A. Mediterranea is smooth and cup-shaped, while
A. crenulate is rounded with a series of fingerlike
projections
• Form of green alga generally found in shallow
tropical seas. It can be found growing in great
abundance along stretches of the overseas highway
to Key West, Florida bordering Florida Bay
• 2 to 10 cm tall and is composed of a single gigantic
cell
• Had a significant role in the development of cell
biology
• When the cap of Acetabularia is cut off at a certain
time in the cell’s life cycle, the cell base grows a
Protoplasm
new cap identical in appearance to the original.
• All cells, either prokaryotic or eukaryotic, are made
• Biologists wondered what kind of cap would form if
of a substance called protoplasm.
they grafted the base of one species onto the stalk
• This name was given early when it was thought
of another.
that protoplasm was a distinct substance such as
• Nucleus is found on the base
water, oxygen, or iron and that one of its properties
was life itself.
- is a mass of proteins, lipids, nucleic acids, and water
within a cell; except for the wall, everything in the cell
is protoplasm, composed of organelles.
Plants take in and use energy
- all organisms require energy for their activities Plasma Membrane
- photosynthesis and cellular respiration - two most - membrane that completely covers the surface of the
important energy-related activities in the living world protoplasm.
- protects cell from surroundings
PHOTOSYNTHESIS CELLULAR RESPIRATION • must be impermeable to harmful materials and
Biological process that Cellular process in which permeable to beneficial ones; therefore, it is
includes the capture of energy of organic selectively permeable.
light energy and its molecules is released for • Molecular pumps in the plasma membrane actively
transformation into biological work transport needed molecules inward and pump
chemical energy of others outward for secretion. Because one side of
organic molecules that the plasma membrane faces the external
are manufactured from environment and the other side faces the cell.
carbon dioxide • permanent storage place for genetic information.
All of that information must be stored in the DNA
inside every nucleus, and the storage must be safe
and permanent.
, • Information is useless unless it can be retrieved and Vacuoles
used. - has just a single membrane, the vacuole
• The nucleus carries out information retrieval by membrane, also called the tonoplast.
making copies of specific parts of the DNA. - often appear to be empty because they store
-the copy is not DNA, but a type of ribonucleic mostly water and salts that cannot be preserved for
acid called messenger RNA. microscopy; however, they sometimes contain
• The nucleus of a eukaryotic cell is always visible crystals, starch, protein bodies, and various
surrounded by a nuclear envelope composed of an types of granules or fibrous materials
outer membrane and an inner membrane. • As a cell grows and enlarges, vacuoles expand and
• The nuclear envelope separates nuclear material merge until there is just one large central vacuole.
from the rest of the cell, and it contains numerous Because it contains primarily water and salts, the
small holes, and nuclear pores, involved in the central vacuole can expand rapidly, forcing the cell
transport of material between the nucleus and the to grow rapidly as well.
rest of the protoplasm. • Animal cells must synthesize complete protoplasm
to grow, but plant cells need only increase the
Nucleus amount of vacuolar water. Over a long period,
• Cell’s control system (brain) plants must produce additional proteins,
• Nuclear pores have a complex structure and exert membranes, and organelles, or else they would
control over the movement of materials. become almost pure water.
• Prokaryotes have no nuclear envelope; instead, • the central vacuole functions in the storage of both
DNA is simply mixed with the rest of the cell nutrient reserves and waste products.
contents.
• Inside every nucleus is one, two, or rarely several
bodies called nucleoli (singular, nucleolus), areas
where the components of ribosomes are
synthesized and partially assembled.
- each ribosome contains a large amount of
ribosomal RNA copied from ribosomal genes in the
chromatin.
• Nuclei are large, complex organelles, and occupy a
major fraction of the volume (up to 50%) of small • A system to excrete wastes never evolved in
dividing cells. plants; instead, metabolic waste products are
• However, most cells enlarge greatly after they stop pumped across the vacuole membrane and stored
dividing and become mature; as cells expand, the permanently in the central vacuole.
nucleus becomes a smaller percentage of cell • The tonoplast is impermeable to these wastes.
volume. - cannot leak back into the cytoplasm where they
would be harmful.
• Holding waste inside forever does not sound like
an optimal situation, but it actually is selectively
advantageous: Because most of these compounds
are noxious and bitter, they deter animals from
eating the plants.
• The water-soluble pigments in many flowers,
fruits, and red beets occur in vacuoles as well.
• In certain conducting cells (sieve tube members in
phloem), the nucleus breaks down during cell
differentiation, and the mature cell functions for
several weeks or months without a nucleus. Our
red blood cells are also enucleated (without a
nucleus) at maturity.
• Several types of plant cells are multinucleated.
PHBIOSC 201 – LEC
- Derived from Greek eu or - Derived from the
Ms. Rody Rica Agdipa
“true” and kary “nucleus”. Greek pro or “before”
- Generally larger and have and kary or “nucleus”.
PLANT CELLS more complex structures. - Genetically smaller
- Genetic material is and simpler.
located in the nucleus, - A cell that lacks the
Coconut tree (Cocos nusifera)
which is bounded by a nucleus and other
• Composed of: (1) a delicate base that anchors it to
membrane. membrane-bounded
a rock or piece of coral (2) long slender stalk (3) cap
- The cytoplasm also organelles.
• Different species of mermaid’s wineglass have caps contains membrane-bound
with different shapes organelles.
• A. Mediterranea is smooth and cup-shaped, while
A. crenulate is rounded with a series of fingerlike
projections
• Form of green alga generally found in shallow
tropical seas. It can be found growing in great
abundance along stretches of the overseas highway
to Key West, Florida bordering Florida Bay
• 2 to 10 cm tall and is composed of a single gigantic
cell
• Had a significant role in the development of cell
biology
• When the cap of Acetabularia is cut off at a certain
time in the cell’s life cycle, the cell base grows a
Protoplasm
new cap identical in appearance to the original.
• All cells, either prokaryotic or eukaryotic, are made
• Biologists wondered what kind of cap would form if
of a substance called protoplasm.
they grafted the base of one species onto the stalk
• This name was given early when it was thought
of another.
that protoplasm was a distinct substance such as
• Nucleus is found on the base
water, oxygen, or iron and that one of its properties
was life itself.
- is a mass of proteins, lipids, nucleic acids, and water
within a cell; except for the wall, everything in the cell
is protoplasm, composed of organelles.
Plants take in and use energy
- all organisms require energy for their activities Plasma Membrane
- photosynthesis and cellular respiration - two most - membrane that completely covers the surface of the
important energy-related activities in the living world protoplasm.
- protects cell from surroundings
PHOTOSYNTHESIS CELLULAR RESPIRATION • must be impermeable to harmful materials and
Biological process that Cellular process in which permeable to beneficial ones; therefore, it is
includes the capture of energy of organic selectively permeable.
light energy and its molecules is released for • Molecular pumps in the plasma membrane actively
transformation into biological work transport needed molecules inward and pump
chemical energy of others outward for secretion. Because one side of
organic molecules that the plasma membrane faces the external
are manufactured from environment and the other side faces the cell.
carbon dioxide • permanent storage place for genetic information.
All of that information must be stored in the DNA
inside every nucleus, and the storage must be safe
and permanent.
, • Information is useless unless it can be retrieved and Vacuoles
used. - has just a single membrane, the vacuole
• The nucleus carries out information retrieval by membrane, also called the tonoplast.
making copies of specific parts of the DNA. - often appear to be empty because they store
-the copy is not DNA, but a type of ribonucleic mostly water and salts that cannot be preserved for
acid called messenger RNA. microscopy; however, they sometimes contain
• The nucleus of a eukaryotic cell is always visible crystals, starch, protein bodies, and various
surrounded by a nuclear envelope composed of an types of granules or fibrous materials
outer membrane and an inner membrane. • As a cell grows and enlarges, vacuoles expand and
• The nuclear envelope separates nuclear material merge until there is just one large central vacuole.
from the rest of the cell, and it contains numerous Because it contains primarily water and salts, the
small holes, and nuclear pores, involved in the central vacuole can expand rapidly, forcing the cell
transport of material between the nucleus and the to grow rapidly as well.
rest of the protoplasm. • Animal cells must synthesize complete protoplasm
to grow, but plant cells need only increase the
Nucleus amount of vacuolar water. Over a long period,
• Cell’s control system (brain) plants must produce additional proteins,
• Nuclear pores have a complex structure and exert membranes, and organelles, or else they would
control over the movement of materials. become almost pure water.
• Prokaryotes have no nuclear envelope; instead, • the central vacuole functions in the storage of both
DNA is simply mixed with the rest of the cell nutrient reserves and waste products.
contents.
• Inside every nucleus is one, two, or rarely several
bodies called nucleoli (singular, nucleolus), areas
where the components of ribosomes are
synthesized and partially assembled.
- each ribosome contains a large amount of
ribosomal RNA copied from ribosomal genes in the
chromatin.
• Nuclei are large, complex organelles, and occupy a
major fraction of the volume (up to 50%) of small • A system to excrete wastes never evolved in
dividing cells. plants; instead, metabolic waste products are
• However, most cells enlarge greatly after they stop pumped across the vacuole membrane and stored
dividing and become mature; as cells expand, the permanently in the central vacuole.
nucleus becomes a smaller percentage of cell • The tonoplast is impermeable to these wastes.
volume. - cannot leak back into the cytoplasm where they
would be harmful.
• Holding waste inside forever does not sound like
an optimal situation, but it actually is selectively
advantageous: Because most of these compounds
are noxious and bitter, they deter animals from
eating the plants.
• The water-soluble pigments in many flowers,
fruits, and red beets occur in vacuoles as well.
• In certain conducting cells (sieve tube members in
phloem), the nucleus breaks down during cell
differentiation, and the mature cell functions for
several weeks or months without a nucleus. Our
red blood cells are also enucleated (without a
nucleus) at maturity.
• Several types of plant cells are multinucleated.
