Chapter 6- overview of cell biology Flashcards
A science that explores living things and life processes
Biology
basic units of all living matter
cells
essential for life
cells
fundamental components of structure, development, growth, and life processes in the human body
biology
-Basic units of all living matter
-Essential for life
-Fundamental components of structure, development, growth, and life processes in the human body
Cells
Exist in a multitude of different forms
Perform many diverse functions for the body
Some exist as freely moving, independent units, whereas others remain in one position as part of the tissues of larger organisms throughout their lifetimes.
If mature, are highly specialized and have predetermined tasks to perform in support of the body
Can move, grow, react, protect themselves and repair damage, regulate life processes, and reproduce
The cell
Requirements of the body
Provide food as a source of raw material for the release of energy
Supply oxygen to help break down the food
Have enough water to transport inorganic substances into and out of the cell
Benefit of proper cell function is that it enables the body to maintain:
homeostasis or equilibrium
Effect of ionizing radiation damaging the components of the cell involved in molecular synthesis beyond repair
what do the cells do:
-cells behave abnormally
-cells die
Cell Chemical Composition
Protoplasm
Organic compounds
Inorganic compounds
Major classes of organic compounds that compose the cell
proteins
carbohydrates
lipids
nucleic acid
what is the basic constituent of all organic matter
carbon
Chemical building material for all living thing
protoplasm
Carries on the complex process of metabolism, the reception and processing of food and oxygen, and the elimination of waste products
protoplasm
consists of organic compounds and inorganic materials either dissolved or suspended in water
protoplasm
formed from some elements, with the four primary elements involved being carbon, hydrogen, oxygen, and nitrogen
protoplasm
water and mineral salts (electrolytes) are the most important inorganic substances
protoplasm
Chemical building material for all living things
Carries on the complex process of metabolism, the reception and processing of food and oxygen, and the elimination of waste products
Consists of organic compounds and inorganic materials either dissolved or suspended in water
Formed from some elements, with the four primary elements involved being carbon, hydrogen, oxygen, and nitrogen
Water and mineral salts (electrolytes) are the most important inorganic substance
protoplasm
Contains the most carbon of all the organic compounds
Constitute approximately 15% of cell content
Essential for growth, the construction of new body tissue, and the repair of injured or debilitated tissue
Formed when amino acids combine into long, chainlike molecular complexes
proteins
Provide the body with its shape and form
Provide a source of heat and energy for the body
structural proteins
-Function as organic catalysts
-Control the cell’s various physiologic activities
-Cause an increase in cellular activity that in turn causes biochemical reactions to occur more rapidly to meet the needs of the cell
enzymatic proteins
how many amino acids are involved in protein production or protein synthesis
22 different amino acids
-Involves 22 different amino acids
-Order of arrangement of these amino acids determines the precise function of each protein molecule
-Type of protein macromolecule that any given cell contains determines the characteristics of that cel
protein production or protein synthesis
-Protein molecules produced by specialized cells in the bone marrow called B lymphocytes
-Produced when other lymphocytes in the body (T lymphocytes) detect the presence of molecules that do not belong to the body
-Chemically attack any foreign invaders or antigens
antibodies
-chemical secretions manufactured by various endocrine glands and carried by the bloodstream to influence the activities of other parts of the body
-regulate body functions such as groth and development
hormones
Can mend damaged molecules and are therefore capable of helping the cell to recover from a small amount of radiation-induced damage
Vital to the survival of cells
Work effectively in both the diagnostic and therapeutic energy ranges
repair enxymes
constitute approx. 2% of cell contents
lipids
make up approx 1% of cell contents
carbohydrates (saccharides)
Make up approximately 1% of cell content
Include starches and various sugars
Range from simple to complex
Function as short-term energy warehouses for the body
Primary purpose is to provide fuel for cell metabolism
Most abundant in the liver and in muscle tissue
Important structural parts of cell walls and intercellular materials
carbohydrates (saccahrides)
Made up of a molecule of glycerin and three molecules of fatty acid
Are organic macromolecules
Are the structural parts of cell membranes
Present in all body tissue
Perform various functions for the body
lipids
comprise approx 1% of the cell
nucleis acids
what are two types of nucleic acid cells contain
DNR and RNA
Comprise approximately 1% of the cell
Are very large, complex macromolecules
Are made up by nucleotides
Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are two types of nucleic acid cells contain
Nucleic ACIDS
-Composed of two long sugar-phosphate chains, which twist around each other in a double-helix configuration and are linked by pairs of nitrogenous organic bases at the sugar molecule of the chain -Hydrogen bonds attach the bases to each other
-Contains all the information the cell needs to function
-Carries the genetic information necessary for cell replication
DNA
-Regulates all cellular activity to direct protein synthesis
-Determines a person’s characteristics by regulating the sequence of amino acids in the person’s constituent proteins during synthesis of these proteins
-Sequence of nitrogenous base pairs in a DNA molecule that constitutes the genetic code
-Has some structural differences when compared with RNA
DNA
-DNA regulates cellular activity indirectly, transmitting its genetic information outside the cell nucleus by reproducing itself in the form of mRNA.
-mRNA leaves the nucleus and, once in the cytoplasm, directs the process of making proteins out of amino acids.
-Differs from DNA in two important ways
-Appears as a single strand of the DNA ladderlike configuration, the ladder being severed in half lengthwise
mRNA
-Receives genetic code from mRNA
-Combines with individual amino acids from different areas of the cell and attaches them to the ribosomes, where amino acids are arranged in specific orders to form chainlike protein molecules
-At least 22 types of tRNA exist, one for each amino acid
-Linking with its corresponding amino acid in the correct order, proteins necessary to provide for the needs of the cell are produced
tRNA
-Another type of RNA
-Its function is to assist in the linking of mRNA to the ribosome to facilitate protein synthesis
Ribosomal RNA
-Tiny rod-shaped bodies that under a microscope appear to be long threadlike structures that become visible only in dividing cells.
-Composed of protein and DNA
-Normal human has 46 different chromosomes (23 pairs) in each somatic (nonreproductive) cell.
-Reproductive cells (germ cells) have only 23 chromosomes each
Chromosomes
-Segments of DNA that serve as the basic units of heredity.
-Each one contains information responsible for directing cytoplasmic activity, controlling growth and development of the cell, and transmitting hereditary information.
-Control the formation of proteins in every cell through the intricate process of genetic coding
Genes
Process of locating and identifying the genes in the genome is called
mapping
The total amount of genetic material (DNA) contained within the chromosomes of a human being
Process of locating and identifying the genes in the genome is called mapping
There are 2.9 billion base pairs in the human genome
These base pairs are arranged into approximately 30,000 genes.
It is estimated that these genes are capable of producing 90,000 different proteins.
Data obtained from the Human Genome Project have allowed us to work on problems in molecular biology
human genome
Compounds that do not contain carbon
Occur in nature independent of living things; they are acids, bases, and salts (electrolytes)
Water and mineral salts are the most important inorganic substances.
Water comprises approximately 80% to 85% of the body’s weight.
Is imperative for the correct amount of water in a cell to be maintained
inorganic compounds
compounds that do not contain carbon
inorganic compounds
monoxygotic twins
idnetical twins
dizygotic twins
fraternal twins
polyzygotic syblings
more than two
Special type of cell division that reduces the number of chromosomes in each daughter cell to half the number of chromosomes in the parent cel
meiosis
four subphases of mitosis
Prophase
Metaphase
Anaphase
Telophase