Download Cellular Anatomy and Physiology

Cellular Anatomy and Physiology
Stacy T. Black
Cells
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All living things (plants, animals) are made up of cells.
The basic unit of structure and function off all living things.
Fundamental life functions occur at the cellular level.
Essential cell functions
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Metabolism
Growth
Irritability
Adaptability
Repair
Reproduction
Cells cont….
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All cells are made out of a chemical material called protoplasm.
Humans contain about 60 to 100 trillion cells.
Vary in size, shape, and function.
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Bone cells, muscle cells, fat cells, blood cells are all types of specialized
cells.
Cells structure is directly related to its function.
Cells cont….
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Cells form tissue
Tissues form organs
Organs form systems
Chemical Configuration of Cells
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Protoplasm contains organic and inorganic compounds
Organic denote chemical substances that contain carbon.
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Proteins
Carbohydrates
Nucleic Acids
Lipids
Chemical Configuration of Cells
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Protoplasm contains 70-85% water and is dependent on type of
cell.
Water makes up about 55-75% of a persons body weight, and for
several reasons is essential to life.
Water in the Body
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Acts as a solvent
Transport medium for substances
Lubricant for joints and digestive tract
Regulates body temp.
Cushions organs such as the brain and lungs.
Proteins
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Comprise 15% of the cell
Composed of carbon, hydrogen, oxygen, and nitrogen.
Found in all parts of living cells
Assists in growth, constructing new tissue, and repairing injured or
worm-out tissue.
A lot in fingernails, hair, cartilage, ligaments, tendons, and muscle.
Proteins cont….
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Amino acids are the building blocks of proteins. 22 different ones
used in the body.
# of amino acids in proteins range from 300 to several thousand.
Insulin, egg white, gelatin, and hemoglobin.
Proteins cont….
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Enzymes are an important group of proteins in all living cells that
act as an organic catalyst.
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Control number of chemical reactions within cell
Affect rate of chemical reactions.
Provide energy to cell
Help make new parts
Control almost every cell process
Lipids
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2% of the cell
Contain carbon, hydrogen, and oxygen.
Exist in all living cells
Store energy
Insulate body from cold
Assist in digestive process
Help lubricate joints
Carbohydrates
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1% of cell
Composed of carbon, hydrogen and oxygen.
Major source of cell energy.
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Found everywhere in body but more predominant in liver and
muscles.
Carbohydrates cont….
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Subdivided into four groups
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Monosaccharides (simple sugars cannot be broken down any further)
Disaccharides (“double sugars” i.e. sucrose, lactose)
Polysaccharides (macromolecules constructed of hundred of thousands of
simple sugar molecules. Starch and cellulose).
Nucleic Acids
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Largest known organic molecule
Composed of carbon, hydrogen, oxygen, and phosphorus
Made from nucleotides
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Form our DNA
Inorganic Compounds
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Mineral Salts are the inorganic substances that are essential for
cell life.
(Na) and (K) are examples of these salts
They maintain osmotic pressure of the cell by maintaining to
correct amount of water in the cell.
Assists in cell energy
Helps conduct nerve impulses.
Cell Structure – Cell Membrane
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Separates the cell’s interior from its exterior surrounding, and from
adjacent cells.
Composed of lipids and proteins arranged in a double layer
Selectively semi-permeable
Lipids allow lipid-soluble materials to diffuse into of out of the cell.
Proteins act as pores, enzymes, or antigens
Cytoplasm
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Watery solution found between the nucleus and cell membrane.
Composed of proteins, lipids, carbohydrates, mineral salts and
water.
Catabolism (converting a complex substance to a simpler
substance), and anabolism (building up of body’s substance takes
place.
Organelles
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Located within the cytoplasm
Help with cell functioning
Include
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Centrioles
Endoplasmic reticulum
Mitochondria
Golgi complex
Lysosomes
Nucleus
The Centrosome and Centrioles
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Centrioles – pair of cylindrical organelles located near the nucleus
Organize spindle fibers during cell mitosis
Contained in a circular body named a centrosome.
Connect to specific chromosomes to aid with the equal
disbursement of these chromosomes to two daughter cells.
Endoplasmic Reticulum
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Extends from the nuclear membrane to the cell membrane.
Assists in channeling proteins and lipids into and out of the nucleus.
Storage area of protein
Rough ER has ribosomes attached to its outer surface.
Smooth ER has no ribosomes; steroid hormone production/inactivation
through enzyme reaction.
The Mitochondria
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Double membrane, oval or rod shaped.
Aerobic (O2 requiring) reactions take place
Contain enzymes to break down carbs, fats, and protein into
energy stored as ATP.
Known as the “powerhouse”
The Golgi Apparatus
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Flat membranous layers
Where carbohydrates are synthesized
Attach to cell membrane to release substances to the cell’s
exterior.
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Abundant in the gastric glands, salivary glands, and pancreatic
glands.
Lysosomes
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Single membrane oval or spherical bodies within the cytoplasm
which contain digestive enzymes that digest protein molecules.
Assist in digesting old, worn-out cell parts, dead cells, bacteria and
foreign material.
If burst, causes cell death.
Nucleus
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Control center “brain” of the cell
Surrounded by nuclear membrane
Contains DNA and protein
46 chromosomes / 23 pair
Divides by mitosis
Nuclear Membrane
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Double layered, opening through which substances can travel
Surrounded by rough ER
The Nucleolus and Ribosomes
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Tiny, spherical-shaped nucleolus contains ribosomes composed of
RNA and protein
Ribosomes Can travel from cells nucleus into the cytoplasm where
it assists in protein synthesis
DNA and RNA
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DNA nucleotide structure composed of phosphate group, a
deoxyribose sugar, and the nitrogenous bases adenine, thymine,
ctyosine, and guanine.
RNA nucleotide consists of a phosphate group, ribose sugar, and
the nitrogenous bases adenine, cytosine, guanine, and uracil
instead of thymine.
DNA
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DNA looks like a coiled ladder
Two strands of nucleotides are a double helix
Sided of ladder formed by alternating phosphate and sugar
molecules.
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Rungs of ladder are formed by pairs of nitrogenous bases;
adenine/thymine, guanine/cytosine
RNA
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Single stranded nucleotide
Uracil pairs with adenine instead of thymine
Produced from DNA in cell nucleus
Functions in cell cytoplasm
Messenger RNA – carries direction and code for protein synthesis
Transfer RNA – carries amino acid molecules from the cytoplasm
to the ribosmoes for protein synthesis.
RNA cont….
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Ribosomal RNA- assists in the linking of messenger RNA to the
ribosomes
Chromosomes and Genes
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Chromosomes are visible in cells that are dividing
Located in the nucleus
Carry genes (genetic material responsible for cytoplasmic activity
and delivering the cells hereditary information.
Chromosomes and Genes cont….
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Sexually producing cells in animals are classified as either germ or
somatic cells.
Cell Growth and Division
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Mitosis – Cell Division
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Interphase
Prophase
Metaphase
Anaphase
Telophase
Mitosis
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Interphase
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Resting and growth stage. Three stages
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G1 – not under going any mitosis, maintaining homeostasis.
S-Phase – “synthesis” stage. DNA replicates itself.
G2 – DNA has been replicated and will enter Prophase
Mitosis
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Prophase – centrioles migrate toward opposite poles of the cell,
producing spindle fibers that extend across the cell’s equator.
Nuclear membrane begins to disappear.
Mitosis
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Metaphase – paired chromosomes line up at the equator of the
cell. Spindle fibers from each centriole attach to the centromeres of
the chromosomes. Nuclear membrane has disappeared.
Mitosis
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Anaphase – the centromeres divide, and the sister chromosomes
detach as they get pulled to an opposite pole. Each chromatid is
regarded as a separate chromosome and now are two complete
and distinct sets.
Mitosis
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Telophase – sets of chromosomes become larger, thinner, and in
distinct as they reach the poles of the cells. DNA unravels to form
chromatins. Formation of new Nuclear Membranes. The nucleolus
reappears.
Meiosis
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Formation of germ cells in the gonads of sexually mature people.
In females called Oogenesis
In males called Spermatogenesis
Sperm and ova have half the number of chromosomes (23),
because if not reduced when sperm and ova united would cause
twice the number of chromosomes (92) instead of (46)