CHAPTER 29 - HUMAN BIOLOGY

atomic level

the effect of x-rays on humans is the result of interaction at the ___________

deposition of energy

these atomic interactions take the form of ionization or excitation or orbital electrons and results in the _______.

molecular change

deposited energy can produce a ___________, the consequences of which can be measurable if the molecule involve is critical.

chemical binding properties

when an atom is ionized, its ___________ changes.

possible

at nearly every stage in the sequence, it is ___________ to repair radiation damage and recover

free electron

this process is reversible. Ionized atoms can become neutral again by attracting a ___________

reversible

this process is ___________. ionized atoms can become neutral again by attracting a free electron.

cells and tissue

___________ and ___________ can regenerate and recover from radiation injury

deterministic effect

if the radiation response increases in severity with increasing radiation dose, it is called a ___________

deterministic effect

it occurs within days after the radiation exposure

stochastic effect

if the incidence of the radiation response increases with increasing radiation dose, it is called as ___________

stochastic effect

this effect is not observed for months or years.

radiobiology

___________ is the study of the effects pf ionizing radiation on biologic tissue.

radiobiologic research

the ultimate goal of ___________ is to accurately describe the effects of radiation on humans so that radiation can be ysed more safely in diagnosis and more effectively in therapy.

atoms

at its most basic level, the human body is composed of ______

atomic level

radiation interacts at the __________.

atomic composition of the body

the ___________ determines the character and degree of radiation interaction that occurs.

radiation response

the molecular and tissue composition defines the nature of the ___________

85%

more than _____ of the body consist of hydrogen and oxygen

molecular change

radiation interaction at the atomic level results in ___________, which can produce a cell that is deficient in terms of normal growth and metabolism.

Robert Hooke

___________, the english schoolmaster, first name the cell as the biologic building block in 1665.

cell

Robert Hooke the english schoolmaster, first name the ____ as the biologic building block in 1665.

Anton van Leeuwenhoek

_________ accurately described a living cell on the basis of his microscopic observation.

cell

it was more than 100 years later, however, in 1838, that Schneider and Schwann showed conclusively that in all plants and animals, _____ are the basic functional units. It is the cell theory.

cell theory

It was more than 100 years later, however, in 1838, that Schneider and Schwann showed conclusively that in all plants and animals, cells are the basic functional units. It is the ________

deoxyribonucleic acid (DNA)

The 1953 Watson and Crick description of the molecular structure of _________ as genetic substance of the cell was a major accomplishments.

macromolecules

_________ are very large molecules that sometimes consist of hundreds of thousands of atoms.

proteins, lipids, and carbohydrates

_____,_____ and _______ are principal classes of organic molecules

DNA

one of the rarest molecules, a nucleic acid concentrated in the nucleus of the cell ______, is considered to be the most critical and radiosensitive target molecule.

Water

______ is the most abundant molecule in the body, an dit is the simpliest.

trace elements and inorganic salts

In addition to water and the macromolecules, some _______ and _______ are essential for proper metabolism.

water

it constitutes approximately 80% of human substance

water molecule

the _________ exist both in the free state and in the bound state, that is, bound to other molecules.

perspiration

during vigorous exercises, the body water is lost through_________ to stabilize temperature and respiration.

homeostasis

water loss must be replaced to maintain ________ which is the concept of the relative constancy of the interval environment of the human body.

Catabolism

water and carbon dioxide are end products in the _______ of macromolecules.

catabolism

it is the process of breaking down into smaller units.

anabolism

_________ the production of large molecules form small and

metabolism

catabolism collective are referred to as _________.

protein

approximately 15% of the molecular composition of the body is _______.

proteins

_______ are long chain macromolecules that consist of a linear sequence of amino acids connected by peptide bonds.

22

________ amino acids are used in protein synthesis.

protein synthesis

________ is the metabolic production of proteins.

linear sequence / arrangement

the _______ of these amino acids determines the precise function of the protein molecule.

proteins

they provide structure and support

protein

muscles are very high in _____ content

proteins

they also function as enzymes, hormones, and antibodies.

enzymes

_____ are molecules that are necessary in small quantities to allow a biochemical reaction to continue even though they do not directly into reaction.

hormones

____ are molecules that exercise regulatory control over some body functions such as growth and development.

hormones

______ are produced and secreted by the endocrine glands, the pituitary, adrenal, thyroid and parathyroid, pancreas and gonads.

Antibodies

_________ constitutes a primary defense mechanism of the body against infection and disease.

antigen

these molecular configuration of an antibody may be precise and designed for attacking a particular type of invasive or infectious agent, the _________.

lipids

_________ are organic macromolecules composed solely of carbon, hydrogen, and oxygen.

lipids

_________ are composed of two types of smaller molecules, glycerol and fatty acids.

glycerol and fatty acids

lipids are composed of two types of smaller molecules, ____ and ______.

lipids

_________ are present in all tissues of the body and are the structural components of cell membranes.

lipids

_________ are often concentrated just under the skin and serve as a thermal insulator from the environment.

lipids

_________ also serve as fuel for the body by providing energy stores.

lipids

it is more difficult to extract energy form _________ than from the other major fuel source, carbohydrates; this relationship is associated with one of the major dilemmas in modern nutrition.

carbohydrates

_________, similar to lipids, are composed solely of carbon, hydrogen, and oxygen, but their structure is different.

body biochemistry

the structural difference of carbohydrates and lipids determines the contribution of the carbohydrate molecule to the _________

saccharides

carbohydrates are also called as _________.

sugar

monosaccharides and disaccharides are _________

starches ; glycogen

Polysaccharides are large and include plant ______ and animal _______

carbohydrates

the chief function of _________ in the body is to provide fuel for cell metabolism.

carbohydrates

some _________ are incorporated into the structure of cells and tissues to provide shape and stability

glycogen

the human polysaccharides, ________, is stored in the tissues of the body and is used as fuel only when quantities of simple sugar, glucose, are inadequate.

tissues of the body

the human polysaccharides, glycogen, is stored in the ________ and is used as fuel only when quantities of simple sugar, glucose, are inadequate.

glucose

_________ is the ultimate molecule that fuels the body.

glucose

Polysaccharides are much more readily transformed into ______.

Deoxyribonucleic acid (DNA) and Ribonucleic Acid (RNA)

Two principal nucleic acid are important to human metabolism: _________ and _________

Deoxyribonucleic acid (DNA)

located principally in the nucleus of the cell, _________, serve as the command or control molecule for cell function.

Deoxyribonucleic acid (DNA)

__________ contains all the hereditary information that represents a cell

RNA

located principally in the cytoplasm, ________ also is found in the nucleus.

1. Messenger RNA

2. Transfer RNA

what are two types of RNA?

biochemical function

mRNA and tRNA are distinguished according to their __________.

protein synthesis

these molecules are involved in the growth and development of the cell through a number of biochemical pathways, most notably, _________

DNA

________ consist of a backbone composed of alternating segments of deoxyribonucleic and phosphate.

water

for each deoxyribose-phosphate conjugate formed, a molecule of _____ is removed.

DNA

________ is the radiation sensitive target molecule

• adenine

• guanine

• thymine

• cytosine

Attached to each deoxyribose molecule is one of four different nitrogen-containing or nitrogenous organic bases _____, ________, ________ and ________

purines

adenine and guanine are _______

pyrimidines

thymine and cytosine are ________

nucleotide

the base sugar - phosphate combination is called a ________

nucleotides

________ are strung together in one long-chain macromolecule.

ladder fashion

human DNA exist as two of these long chains attached together in ________

Hydrogen Bonds

The side rails of the ladder are the alternating sugar phosphate molecules, and the rungs of the ladder consist of bases joined together by ________.

double-helix configuration

The DNA is twisted into a ladder formation called a ________

guanine

The sequence of base bonding is limited to adenines bonded to thymine and cytosines bonded to ________

RNA

structurally, ________ resembles DNA

ribose

In RNA, the sugar component is ________ rather than deoxiribose.

uracil

In RNA, ________ replaces thymine as a base component.

single

RNA forms a ________ helix, not a double helix

intricate cellular structures

the principal molecular components of the human body are made of ________

nucleus and cytoplasm

two major structures of the cell are the________ and ________.

DNA

the principal molecular component of the nucleus is ________

nucleolus

most of the RNA is contained in a rounded structure, the ________.

nucleolus

the ________ often is attached to the nuclear membrane, a doubled-walled structure that are some locations is connected to the endoplasmic reticulum.

endoplasmic reticulum

the ________ is a channel or a series o channels that allows the nucleus to communicate with the cytoplasm.

mitochondria

The large ben-shaped structures are ________.