Human Biology Test # 1

anything that has mass and occupies space it is composed by elements

cannot be broken down to a simpler form, periodic table of elements list of them

the study of matter

the smallest functional unit of elements

is the central core of the atom and is made of positively charged protons and a nearly equal number of neutral particles called neutrons

positively charged and has mass

neutral and has mass

negatively charged particles that surround the atom, has hardly any mass and affect how an atom interacts with another element

neutrally charged

one or two letters
exp: Na for sodium and O for oxygen

the number of protons

roughly the same number of protons plus neutrons

atoms with either more or fewer neutrons than the usual number for that element, they have the same atomic number but a different atomic mass(diff number of neutrons.)

unstable isotopes that give off energy in the form of radiation

exp: Carbon 14 used for dating fossils, diagnostic imaging, cancer treatment, power supply for implants such as cardiac pacemakers

the capacity to do work

stored energy

energy in motion

more potential energy, (electrons have potential energy)

covalent
ionic
hydrogen

STRONG bonds- a bond in which the sharing of electrons between atoms result in each atom having a maximally filled outer shell of electrons

when electrons among atoms are shared equally

when atoms dont share electrons equally

MODERATE bond- the bond between two oppositely charged ions (atoms or molecules that were formed by the permanent transfer if one or more electrons)

forms when an atom loses electrons

forms when if an atom gains electrons

WEAK bond and is formed between polar molecules

*is polar
*water is liquid at body temperature
*water can absorb and hod heat energy
*water is the biological solvent
*water helps regulate body temperature

liquid in which other substances dissolve

any dissolved substance

polar molecules that are attracted to water and interact easily with water

non polar neutral molecules that do not interact with or dissolve in water

one of the most important ions in the body...a single proton w/out an electron)

donate hydrogen ions(protons)
into a solutions
exp: dropping acid in water

accept hydrogen ions (protons)
lower hydrogen ion concentration in solution

a measure of hydrogen ion concentration
ranges from 0-14
Acid: pH <7
Neutral pH=7
Basic: pH >7

7.4

a buffer minimizes the change in pH and are essential to our ability to maintain homeostasis.

one of the most important buffer pairs in body fluids such as blood.

compromises 18% of the body by weight
forms four covalent bonds
can form a single or double bonds
can build micro- or macromolecules

removes equivalent of a water molecule to link molecular untis
requires energy
builds macro molecules from smaller sub units

adds the equivalent of a water molecule to break apart macromolecules
releases energy

carbohydrates
lipids
proteins
nucleic acids

they are used for energy and structural support

simple sugars
glucose
fructose
galactose
ribose
deoxyribose

more than one momosaccharide linked together..this can be done through dehydration process

dissaccharides are two monosaccharides linked together
exp:
sucrose: glucose+ fructose
maltose: glucose + glucose
lactose: glucose + galactose

glycogen

complex carbohydrates- thousands of monosaccharides joined in chains and branches

starch, we can use it for energy by breaking it down to glucose

indigestible polysaccharide made in plants for structural support

they are insoluble in water.

triglycerides;energy storage molecules
phospholips: cell membrane structure
steroids: carbon-based ring structures

a lipid, also known as fat and oil
fatty acids
*saturated in fats
*unsaturated in oils
stored in adipose tissue
energy storage molecules

lipid
Glyserol + two fatty acids and phosphate group
One end of molecule is water insoluble(hydrophilic)
other end of molecule is water insoluble (hydrophobic)
PRIMARY COMPONENT OF CELL MEMBREANE

lipid- composed of four carbon rings
exp:
cholesterol
hormones
-estrogen
-testosterone

a long chains of subunits called aminoacids that are joined by peptide bonds

primary structure
secondary
tertiary
quaternary

amino acid sequence
stabilized by peptide bonds

alpha helix
beta pleated sheets
stabilized by hydrogen bonds

three denominational shape
stabilized by disulfide and hydrogen bonds
creates polar and non-polar areas in molecule

two or more polypeptide chains are associated

denaturation
can be damaged by temperature or changes in pH
leads to loss of biological function

they facilitate biochemical reactions
Proteins
Function as biological catalysts
-speed up chemical reactions
-are not altered or consumed by the reaction
WITHOUT ENZYMES MANY BIOCHEMICAL REACTIONS WOULD NOT PROCEED QUICKLY ENOUGH TO SUSTAIN LIFE!

temperature
pH
Ion condition
presence of inhibitors

are long chains containing sub-units called neuclotides. they store genetic information

DNA- deoxyribosenucleic acid
RNA- ribonucleic acid
they store genetic information and provide information used in the making proteins

building blocks of nucleic acids
each nucleotide contain 5 carbon sugar

deoxyribose

ribose

double stranded
neclotides contain
deoxyribose (sugar)
nitrogenous bases
adenine
guanine
cytosine
thymine

single stranded
neuclotides contain ribose
nitrogenous bases
-adenine
-guanine
-cytosine
-uracil

DNA- instructions for making RNA
RNA- instructions for making proteins
Proteins: directs most of life's processes
DNA--> RNA --> Proteins

adenosine triphosphate i
carries energy
universal energy group
bonds between phosphate groups that contain potential energy
breaking bonds releases energy
TP--> ADP + P + energy

*all living things
*a single cell is the smallest unit that exhibits all of the characteristics of life
*all cells come only from preexisting cells

they are located in the plasma membrane
have no nucleus
the cytoplasm fluid is in the membrane
has no true organelles

All human cells are eukaryotic
have a plasma membrane
nucleus:information center
Cytoplasm fluid within a membrane
orgaganelles:structured with specialized functions

microscopic cannot be seen without magnification

1000X's and is the earliest microscope

up to 100,000X's
100X's greater than a light microscope
the magnification is sufficiently high that one can see the structural details of organelles within cells.

up to 100,000X
it gives a three dimensional look to the surface of the object.

to stay efficient
*small cells have a higher surface volume ratio
*high surface: volume ratio problems efficiency in
-acquisition of nutrients
-disposal of wastes

a wall called the plasma membrane surrounds the cell
separates a cell from its enviroment
selectively permeable
-permits movement of some substance into and out of the cell, but blocks others
Enables transfer of information between environment and cell

a lipid bilayer
-phospholipids:polar head and nonpolar tail
-cholesterol:makes membrane
a bit more regid
-proteins:provide means of transport through membrane
-carbohydrates:recognition patterns for cells and organisms
*non rigid
*fluid mosaic

passive transport
active transport
bulk transport

cell does not need to expend energy bc it moves through a concentration gradient
-diffusion through lipid layer
-osmosis
-facilitated transport

cell must expend energy by moving moving substances from a lower concentration to an area of higher concentration
-requires ATP

-involves membranous vesicles to move larger substance
-endocytosis
-exocytosis

moves materials is bulks into the cell

moves material in bulk out of the cell

sodium-potassium pump- expels unwanted ions,keeps needed ones and maintains cell volume.
ATP is used to expel3 Na+ ions into the cell and 2 K+ into the cell

increase in cell volume(decreasing pumping)

decrease in volume(increasing pumping)

extracellular and intracellular ionic concentrations are equal
cells maintain a normal volume in isotonic extracellular fluids
-regulatory mechanisms maintain extracellular fluid that is isotonic with intracellular fluid

relative concentration of solutes in two fluids

hypertonic
hypotonic

-extracellular ionic concentration higher than intracellular
water will diffuse out of cell
-cell will shrink and die

-extracellular ionic concentration lower than intracellular
-water will diffuse into cell
-cell may swell and burst

site of protein synthesis
free floating in cytoplasm
attached to outer surface of endoplasmic reticulum

Rough ER
-has ribosomes on surface
-protein manufacturing, modifications
Smooth ER
-no ribosomes on surface
-lipid synthesis
-packages the proteins

refines synthesized products
packaging and shipping center
products are packaged into vesicles and shipped to other locations within cell membrane for export

contains powerful digestive enzymes, they perform housekeeping tasks like removing damaged mitochondria and other cellular debris.

"power plant of the cell
Surrounded by double membrane
utilizes oxygen to produce Co2
generates ATP

triglycerides
-long-term energy storage in animals

carbohydrate storage
short term storage in animals

consist of microtubes and microfilaments...forms a framework for the soft plasma membrane and it also supports and anchors the other structure w/in cell

cilia- are hairlike particles in a few cells
(2-10 microns long) moves material along the surface of with a brushing motion
flagella-(200 microns long) are ONLY found in sperm cells and allows them to swim

requires enzymes
breakdown of molecules
may release energy
used in breaking down nutrients and recycling all components
used to access energy storage

it provides energy for the cell
energy in glucose is used to generate ATP
in absense of glucose other carbs, fats, proteins, can be catabolized to generate ATP

glycolisis
preparatory step
citric acid cycle
electron transport system

occurs int eh cytoplasm
series of ten reactions that split glucose into two molecules of pyruvic acid
2 ATP are produced
high energy electrons and hydrogen ions are removed and picked up by a coenzyme NAD+ forming NADH

occurs in mitochondria
also known as krebs cycle
extracts high energy electrons to form NADH and FADH2 produces 2 ATP and carbon dioxide