Chemical Level Of Life Flashcards
atom
the smallest unit of an element that exists as a stable entity
element
a substance containing only one type of atom
eg: iron
compound
When a substance contains two or more different types of atom
water
our bodies are composed almost entirely of which 4 compounds
carbon, hydrogen, oxygen, and nitrogen.
There are other, smaller amounts of as well which make up only 4% of our body weight, these include sodium, potassium, calcium, and phosphorus
Atomic number
the number of protons in the nuclei of its atoms
atomic weight
the sum of its protons and neutrons in the atomic nucleus
overall chemistry of living things depends upon
the active ability of atoms to reach and combine with one another to produce a wide range of molecules required for biological diversity.
An atom is considered reactive when
when at atom does not have a stable number of electrons in its outermost shell, and may donate, receive, or share electrons with one or more other atoms in order to achieve stability of function
Isotopes
atoms of an element in which there is a different number of neutrons in the nucleus
types of chemical bonds
covalent
ionic
Covalent bonds
formed when atoms share their electrons with each other.
ionic bonds
weaker than covalent bonds and are formed when electrons are transferred from one atom to another.
electrolyte
made up of an ionic compound which is dissolved in water.
it has the capacity to conduct electricity.
why are electrolytes important to the human body
- Conduct electricity which is essential for muscle and nervous system function.
- Exert osmotic pressure, keeping the body’s fluids in their own compartments.
- Act as a buffer to resist pH changes in body fluids.
- Important electrolytes in the body include sodium, chloride, potassium, calcium, bicarbonate, and phosphate.
molecular weight
the sum of the atomic weights of the elements forming its molecules
dissociate
they separate into ions and become surrounded by water molecules
what dissociates?
inorganic acids, bases, or salts when they dissolve in water
acid
a substance that dissociates into one or more hydrogen ions and one or more anions.
base
removes positively charged hydrogen from a solution and is therefore a proton acceptor.
many dissociate into one more more hydroxide ions and one or more cations.
salt
when dissolved in water, dissociates into cations and anions, neither of which is a positively charged hydrogen ion or an hydroxide ion
why are salts important in the body?
electrolytes that are important for carrying electrical currants, especially in nerve and muscular tissues.
how do salts form?
when acids and bases react with one another
pH
a scale used to specify the acidity or basicity of an aqueous solution
logarithmic and inversely indicates the concentration of hydrogen ions in the solution
what are Carbohydrates made of
(sugars and starches) are composed of carbon, oxygen, and hydrogen
Organic molecules
glycosidic link
the bond formed when two sugars combine to form a bigger sugar & a water molecule is expelled
Glucose
the main form in which sugar is used by cells, is a monosaccharide.
Monosaccharides
can be linked together to form bigger sugars, ranging in size from two sugar units (disaccharides) to long chains containing many thousands of monosaccharides (polysaccharides).
how is glucose metabolized?
either in the presence or absence of oxygen, but the process is much more efficient when oxygen is used.
Carbohydrate sugars do the following:
- Provide a ready source of energy to fuel cell metabolism.
- Provide a form of energy storage.
- Form an integral part of the structure of DNA and RNA.
- Act as receptors on the cell surface, allowing the cell to recognize other molecules and cells.
basic relationship of carbohydrates
carbon coupled with water molecules
basic relationship of carbohydrates
carbon coupled with water molecules
how are carbohydrates produced
by photosynthesis in plants
carbs produce what type of energy?
both an immediate
and time-released energy source as they are digested easily and then consistently
metabolized in the blood stream.
amino acids always contain
carbon, hydrogen, oxygen, and nitrogen
maybe sulfur
building blocks of protein in human biochemistry
20 amino acids
important groups of biologically
active substances that are proteins
carrier molecules (hemoglobin), enzymes, many hormones such as insulin, and antibodies
what do proteins do
essential for growth and development
provides the body with energy, and is needed for the manufacturing of hormones,
antibodies, enzymes, and tissues
maintain the proper acid-alkali
balance in the body
nonessential amino acids
they do not have to come from the diet because they can be synthesized by the body from other amino acids.
essential amino acids
the body cannot synthesize them, and therefore must obtain them from the diet
cachexia
presents as weight loss, muscle atrophy, and severe fatigue and can result
from a poor dietary protein intake
Lipids
the inability for lipids to mix with water, making them hydrophobic.
most commonly made up of carbon, hydrogen, and
oxygen atoms
most important lipid groups
- Phospholipids - integral to cell membrane and cell wall structures.
- Certain fat soluble vitamins such as A, D, E, and K.
- Fats (triglycerides)
- Prostaglandins
- Cholesterol
Prostaglandins
chemicals derived from fatty acids that are involved in inflammation and other processes.
Cholesterol
a lipid made in the liver, an integral part of cell membranes and steroid based hormones
Fats (triglycerides)
a key energy source stored in adipose tissue, also a body insulator and protector of internal organs.
Nucleic acids
largest molecules in the body and are built from nucleotides.
include deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).
ATP
nucleotide that contains ribose (the sugar unit), adenine (the base), and three phosphate groups attached to the ribose
energy center for the body, or cellular energy
The body needs chemical energy - main expenses
- Drive synthetic reactions (i. e. building biological molecules)
- Fuel movement (locomotion)
- Transport substances across membranes
Enzymes
proteins that act as catalysts for biochemical reactions - that is, they speed the reaction up but do not physically change with the reaction itself, therefore
the body can use them over and over again.
conditions for enzyme action
temperature
pH
Some enzymes require the presence of a cofactor, an ion or small molecule that
allows the enzyme to bind to its substrate
anabolic reaction
When an enzyme catalyzes the combination of two or more substrates into a
larger product
catabolic reactions
e breaking down the substrate into smaller products, as occurs during the digestion of foods.
Passive movement
Substances will always travel from an area of high concentration to one of low
concentration, assuming that there is no barrier in the way
how passive movement happens
diffusion or osmosis
Diffusion
the movement of a chemical substance from an area of high
concentration to an area of low concentration
occurs mainly in gases, liquids,
and solutions
what affects diffusion rate
temperature
concentration
osmosis
diffusion of water down its concentration gradient
isotonic
a solution having the same osmotic pressure as some other solution, especially one in a cell or a body fluid
extracellular fluid (ECF)
consists mainly of blood, plasma, lymph, cerebrospinal fluid, and fluid in the interstitial spaces of the body
role of extracellular fluid (ECF)
mainly in lubrication, and they include joint (synovial) fluid, pericardial fluid (around the heart), and pleural fluid (around the lungs)
intracellular fluid (tissue fluid)
bathes all the cells of the body
except the outer layers or the skin
composition of intracellular fluid (ICF)
largely controlled by the cell itself, because there are selective uptake and discharge mechanisms present in the cell
membrane
