Module 1.1: Intro to Life Science for Midwifery Flashcards
What does chemistry examine?
- the properties, composition, and structure of elements and compounds
- how these change
- the energy released or absorbed when they change
What is a compound?
Substances formed by two or more
elements
What is an element?
A substance that cannot be separated into
simpler substances by chemical means
What does an element consist of?
An element consists of an atom with a unique combination of protons, neutrons, and electrons
What are the three classifications of elements?
major, minor, trace
what percentage do major elements make up?
96%
what are some examples of major elements?
Oxygen, Carbon, Hydrogen, Nitrogen
what percentage do minor elements make up?
3.6%
what are some examples of minor elements?
Calcium, Phosphorous, Potassium,
Sulfur, Sodium, Chlorine,
Magnesium, Iron
what percentage do trace elements make up?
0.4%
what are some examples of trace elements?
Aluminium, Cobalt, Copper, Fluorine,
Iodine, Manganese, Molybdenum,
Selenium, Silicon, Tin, and Zinc
what is an atom?
- Basic building block of chemistry
- Smallest unit of an element
what does an atom consist of?
protons, neutrons, and electrons
what is located within the nucleus?
protons and neutrons
what surrounds the nucleus?
electrons
how do electrons act?
surround the nucleus, not static but rather always in motion
what is the bohr atom model?
Visualizes electron
shells as concentric circles
surrounding the nucleus
when is an atom considered neutral? (Generally)
of electrons = # of protons = ‘0’
charge
when are atoms not neutral?
Filling the shells with electrons push
atoms to have charges and react with
one another
how many electrons can the first shell hold? the second shell?
first shell: 2 electrons
second shell: 8 electrons
when is an atom stable and unlikely to form a bond with another atom?
when its outer electron shell is full
what is the octet rule?
- Atoms will tend to form bonds to achieve a full outer shell of 8 electrons
- To do this, they can lose, gain or share electrons
between atoms
what is the atomic number? where is it found?
the number of protons in the
nucleus. top left corner
what is the mass number?
the sum of its protons and
neutrons
what is an isotope?
Variation of an element that has
the same number of protons BUT
different number of neutrons in
its nucleus
how do the atomic number and mass number differ in isotopes?
Same atomic number but
mass number differs because
of varying number of
neutrons
why do all isotopes have the same chemical properties?
Have the same number of
electrons (which determines
its chemical properties)
what types of isotopes are radioactive?
unstable isotopes
what are the two kinds of isotopes?
stable and unstable
explain how radioactive isotopes are created
- Nuclei spontaneously change (decay) over time to a more stable configuration
- As they decay, they emit radiation and particles
what is atomic mass
average mass of all isotopes of
an element
what is atomic mass measured in?
Measured in daltons (atomic mass units)
what is an ion?
A particle with either a
* Negative (-) Charge or
* Positive (+) Charge
what makes an ion?
an unequal number of electrons compared to
protons
Cl- = chlorine ion = -1 charge
did this gain or lose an electron?
gain
Ca2+ = calcium ion = +2 charge
did this gain or lose electrons?
lose
what is a free radical?
An atom with an unpaired electron in its outermost shell
how do free radicals behave?
the atom is unstable, highly reaction and
destructive to other tissues
what is an example of a free radical?
Oxygen can form free radicals in the body,
which can damage cells
what is the effect of a free radical?
Cause damage to cell membranes, DNA, can alter
biochemical compounds
how can free radicals become stable?
- By giving up an electron or “stealing” an electron from another molecule, breaking apart important body molecules
- When they steal an electron, they may create a new free radical
what produce free radicals?
- Ultraviolet light in sunlight
- X-rays
- Normal metabolic reactions
- Air pollution
- Cigarette smoke
- Alcohol
- Drugs
what diseases are linked to free radicals?
- Premature aging
- Pre-eclampsia
- Fetal alcohol syndrome
how can damage of free radicals be slowed?
Damage may be slowed with antioxidants such as vitamins C and E and selenium
what is a cofactor?
a compound that helps enzymes function (mainly trace elements)
how are cofactors obtained?
normally through diet so theres minimal concern about deficiency
what are some examples of cofactors?
cobalt, copper, iodine, manganese, molybdenum, zine, selenium
what is florine used for?
seen as fluoride and used to prevent tooth decay and make enamel stronger
how many elements are there and how many of them are found on nature?
118
98
what is hydrogen important for?
organic molecule
what are sodium and potassium important for?
electrolytes
what are magnesium and calcium important for?
teeth and bones + electrolytes
what is calcium important for?
smooth muscles contraction potentials + electrolytes
what is iron important for?
anemia/blood related disorders
what is carbon important for?
backbone of organic molecules
what is nitrogen important for?
carbon compounds like amino acids
what is phosphorous important for?
phosphate + magnesium = bone
what is oxygen important for?
oxidative metabolism
what is sulfur important for?
Protein structure (disulfide bonds + cross bridging)
what is chorine important for?
electrolytes
What is iodine important for?
formation of thyroid hormone
what is an example of a radio isotope?
iodine-123 emits gamma radiation used for imaging
what are some harmful effects of radio isotopes?
cause cancer or disease (ex. radon 222 is associated w lung cancer in non-smokers)
What are some beneficial effects of radio isotopes?
medical imaging for diagnosis or treatment (ex. imagine thyroid (I-123) treatments for hyperthyroidism (I-131) cancer
