CELL BIOLOGY AND BIOCHEMISTRY

1. Cell biology
and
Biochemistry
Name: Mili Bhardwaj
Registration number:
16BCB0076
2/12/2018
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2. 2/12/2018
Cell nucleus
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3. Introduction
• In cell biology, the nucleus is a membrane-enclosed organelle
found in eukaryotic cells.
• Eukaryotes usually have a single nucleus.
• But a few cell types, such as mammalian red blood cells, have
no nuclei, and a few others have many.
• Human skeletal muscle cells have more than one nucleus, as
do eukaryotes like fungi.
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An introduction to cell nucleus
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4. The cell nucleus is a
membrane bound
structure that
contains the cell's
hereditary
information and
controls the cell's
growth and
reproduction. It is
the command center
of a
eukaryotic cell and
is commonly the
most
prominent organelle
in a cell.
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Inner view of Cell Nucleus
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5. Distinguishing characteristics• bound by a double membrane called the nuclear envelope
• the nuclear envelope consists of phospholipids that form a
lipid bilayer.
• The nucleus is the organelle which houses chromosomes.
• The nuclear envelope is connected with the endoplasmic
reticulum (ER)in such a way that the internal compartment
of the nuclear envelope is continuous with the lumen of the
ER.
• Chromosomes consist of DNA, which contains heredity
information and instructions for cell growth, development, and
reproduction.
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6. Nucleoplasm
• Nucleoplasm is the gelatinous substance within the nuclear
envelope.
• composed mainly of water with dissolved salts, enzymes, and
organic molecules suspended within.
• Nucleoplasm also supports the nucleus by helping to maintain
its shape.
• Substances are exchanged between the cytoplasm and
nucleoplasm through nuclear pores.
• Additionally, nucleoplasm provides a medium by which
materials, such as enzymes and nucleotides (DNA and RNA
subunits), can be transported throughout the nucleus.
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Components of the Cell
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7. Nucleolus
• membrane-less structure composed of RNA
and proteins called the nucleolus.
• contains nucleolar organizers, which are parts of
chromosomes with the genes for ribosome synthesis on them.
• helps to synthesize ribosomes by transcribing and assembling
ribosomal RNA subunits.
• These subunits join together to form a ribosome during
protein synthesis.
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Components of the Cell
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8. Protein synthesis
• The nucleus regulates the synthesis of proteins in the
cytoplasm through the use of messenger RNA (mRNA)
• Messenger RNA is a transcribed DNA segment that serves as a
template for protein production
• It is produced in the nucleus and travels to the cytoplasm
through the nuclear pores of the nuclear envelope.
• Once in the cytoplasm, ribosomes and another RNA molecule
called transfer RNA work together to translate mRNA to
produce proteins.
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Functions
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Functions
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10. Chromatin and chromosomes• Packed inside the nucleus of every human cell is nearly 6 feet
of DNA, which is divided into 46 individual molecules, one for
each chromosome and each about 1.5 inches long.
• Packing all this material into a microscopic cell nucleus is an
extraordinary feat of packaging.
• For DNA to function, it can't be crammed into the nucleus like
a ball of string. Instead, it is combined with proteins and
organized into a precise, compact structure, a dense string-
like fiber called chromatin.
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Functions
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Functions
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12. Nuclear pores
• The nuclear envelope is perforated with holes called nuclear
pores.
• These pores regulate the passage of molecules between the
nucleus and cytoplasm, permitting some to pass through the
membrane, but not others.
• Building blocks for building DNA and RNA are allowed into the
nucleus as well as molecules that provide the energy for
constructing genetic material.
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14. Applications of Cell Nucleus
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Applications
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15. Application od Cell Nucleus
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