Lesson 1C Flashcards
chemistry of life elements
carbon, hydrogen, oxygen, nitrogen, phosphorous, sodium
Main chemical elements in the body
major elements (96%), lesser elements (3.6%), trace elements (0.4%)
Major elements
oxygen - 65.0
carbon - 18.5
Hydrogen - 9.5
Nitrogen - 3.2
Lesser elements
calcium - 1.5
phosphorous - 1.0
potassium - 0.35
sulfur - 0.25
sodium - 0.2
chlorine - 0.2
magnesium - 0.1
iron - 0.005
trace elements
aluminum, boron, chromium, cobalt, copper, fluorine, iodine, manganese, molybdenum, selenium, silicon, tin, vanadium, and zinc
force of attraction that holds together ions with opposite charges
ionic bonds
cation
positively charged ion
anion
negatively charged ion
ionic bonds are found mainly ____ and ____, where they give great strength
teeth and bones
an ionic compound that breaks apart into positive and negative ions in a solution
electrolyte
forms when two or more atoms share electrons rather than gaining or losing them
covalent bonds
the larger the number of electron pairs shared between two atoms, the _____ the covalent bond
stronger
forms when a hydrogen atoms with a partial positive charge attracts the partial negative charge of neighboring electronegative atoms, most often larger ______ or _______ atoms.
hydrogen bonds
oxygen or nitrogen
occurs when new bonds form or old bonds break between atoms
chemical reactions
reactants (starting substances)
products (ending substances)
the number of atoms of each element is the ____ before and after a chemical reaction
same
2 principal forms of energy
potential and kinetic energy
capacity to do work
energy
en = in
ergy = work
energy cannot be created or destroyed…just transferred or converted
law of conservation of energy
chemical energy
carbohydrates
fats
chemical waste
carbon dioxide
water
body’s energy currency
ATP
collision energy needed to break the chemical bonds of the reactants
activation energy
activation energy is influence by
concentration and temperature
chemical compounds that speed up chemical reactions by lowering the activation energy: enzymes
catalyst
types of chemical reactions
synthesis reaction - anabolism
decomposition reaction - catabolism
exchange reactions
reversible reactions
oxidation-reduction reactions
when two or more atoms, ions, or molecules combine to form new and larger molecules
synthesis reactions - anabolism
(dehydration reaction)
split up large molecules into smaller atoms, ions, or molecules
decomposition reactions - catabolism
consist of both synthesis and decomposition reactions: switched partners
exchange reactions
products can revert to the original reactants
reversible reactions
always parallel; when one substance is oxidized, another is reduced at the same time
oxidation-reduction reactions
2 metabolism
anabolism (combine) and catabolism (decompose)
absorb more energy than release
endorgonic
release more energy than absorb
exergonic
large organic (carbon-containing) molecules
major macromolecules
a very abundant element
carbon
major macromolecules
carbon
lipids
proteins
nucleic acids
many macromolecules start as small _____ that grow into large ______
small monomers
large polymers
carbohydrates elements
carbon
hydrogen
oxygen
types of carbohydrates
monosaccharides (glucose, fructose)
disaccharides (sucrose)
polysaccharides (starch, glycogen, cellulose, chitin)
Functions of carbohydrates
- energy supply and storage
- structural support
- provides dietary fiber
- deoxyribose and ribose in DNA AND RNA
fatty compounds made of C, H, O; don’t interact with water (hydrophobic)
cell membranes are composed of two lipid layers, which keep water from crossing
lipids
polymers made up of fatty acid monomers
fatty acids have oily “tails” and polar “heads”
lipids
lipids in water will arrange themselves to hide their
hydrophobic tails
cell membranes are composed of a
phospholipid bi-layer
other lipids
waxes
oils
steroids
lipid functions
- long term energy supply and storage
- main structural component of cell membranes (as phospholipids and cholesterol)
- hormones such as testosterone and estradiol
the genetic material in any cell
nucleic acids (deoxyribonucleic acids and ribonucleic acids)
nucleic acids
DNA
RNA
Polymer chains composed of a combination of 5 different monomers
(lipids) monomers are called _______
nucleotides
monomers/nucleotides
adenine
cytosine
guanine
thymine (DNA only)
uracil (RNA only)
millions of monomers long, wound in a double helix
nucleic acid polymers
structural building blocks of cells in all tissues (not just muscle)
polymers composed of 300-100k monomers
proteins
(proteins) monomers are called ______
amino acid
how many amino acids must come from our diet?
20 amino acids
the order of amino acids making up the polymer string
primary structure
helixes and sheets of the polymer string folding on itself
secondary structure
globs of sheet and helixes folding around each other
tertiary structure
individual proteins bound to each other to form a multi-protein unit with its own function
quaternary structure
carries oxygen in the blood
hemoglobin
contain several hundred molecules which transport oxygen
red blood cells
oxygen binds to ____ on the hemoglobin molecule
heme
______ in skeletal muscle cells
actin fibers
make up the cell cytoskeleton
proteins
______ to copy and repair DNA
enzymes
who discovered cells?
anton van leewenhoek
german botanist who stated that “all plants are composed of cells”
Matthias Schleiden
1838
discovered that animals are made up of cells
Theodor Schwann
1838
discovered that humans are made up of cells
Rudolf Virchow
The COMBINED work of Schleiden, Schwann, and Virchow make up the modern
CELL THEORY.
basic structural and functional unit of living organisms
cell
According to the __________, the biochemical activities of cells are dictated by the relative number of their specific subcellular structures.
principle of complementarity
According to the principle of complementarity, the biochemical activities of cells are dictated by the??
relative number of their specific subcellular structures
Continuity of life has a
cellular basis
The Cell Theory states that:
- All living things are composed of a cell or cells.
- Cells are the basic unit of life.
- All cells come from preexisting cells.
Limits in Cellular and Multicellularity
cell size
a cell has three main regions or parts:
Nucleus
Cytoplasm
Plasma (Cell) membrane
one of the membranes of the cytoplasm which keeps it all together, also helps to control what can get in and out of the cell
cell membrane
contains the chromosomes where inherited information is stored
nucleus
lots of membranes made from proteins and fats; tiny fluid filled spaces form in the folds of the membranes
cytoplasm
Most cells are composed of four elements:
Carbon
Hydrogen
Oxygen
Nitrogen
Cells are about _____% water
60-80%
function of the cell
ability to metabolize
digest foods
dispose wastes
reproduce
grow
move
respond to stimulus
control center of the cell; contains genetic material
nucleus
3 regions of nucleus
nuclear membrane
nucleolus
chromatin
barrier of nucleus; consists of a double phospholipid (bi-layer) of membrane; contain nuclear pores allowing material exchange with the rest of the cell
nuclear membrane
nucleus contain one or more ______; a non-membrane bound organelle taking part in synthesis of ribosomes, including processing of rRNA and the assembly of them into ribosome units
nucleoli
the nucleus is also involved in several other cellular processes such as mitosis, stress response, and cell cycle regulation
nucleoli
composed of DNA & proteins; scattered throughout the nucleus; condenses to form chromosomes when the cell division starts
chromatin
barrier for cell contents; double phospholipid layer (hydrophilic heads + hydrophobic tails)
plasma membrane
forms the cell’s flexible outer surface, separating the cell’s internal environment (everything inside the cell) from the external environment (everything outside the cell).
It is a selective barrier that regulates the flow of materials into and out of a cell.
plasma membrane
other materials in plasma membrane
protein
cholesterol
glycoproteins
finger-like projections that increase surface area for absorption
microvilli
tight junctions
- Impermeable junctions
- Bind cells together into leakproof sheets
desmosomes & hemidesmosomes
- Anchoring junctions that prevent cells from being pulled apart
gap junctions
- Allow communication between cells
membrane junctions
Impermeable junctions
Bind cells together into leakproof sheets
tight junctions
Allow communication between cells
gap junctions
Anchoring junctions that prevent cells from being pulled apart
desmosomes
material outside nucleus and inside the plasma membrane
cytoplasm
fluid that contains other elements
Viscous semi-transparent fluid that suspends other elements
cytosol
metabolic machinery of the cell
“Little organs” that perform functions for the cell
organelles
non-functioning units (lipids…)
Chemical substances such as stored nutrients or cell products
inclusions
cytoplasmic organelles
ribosomes
rough and smooth ER
golgi apparatus
mitochondria
lysosomes
peroxisomes
cytoskeleton
centrioles
- made of protein and RNA
- sites of protein synthesis
- found at two locations
- free in the cytoplasm
- attached to rough endoplasmic reti
ribosomes
fluid-filled tubules for carrying substances
Structure: a system of fluid-filled tunnels (or canals) that coil and twist through the cytoplasm
Function: serves as a mini circulatory system or intercellular highway (a path along which molecules move from one part of the cell to another)
endoplasmic reticulum
several types of packages of proteins
- secretory vesicles
- cell membrane components
- lysosomes
modifies and packages proteins; produces several types of packages
Structure: stacked flat sacs
Function: receives proteins from the rER and distributes them to other organelles or out of the cell (receiving, processing, packaging, and shipping)
golgi apparatus
powerhouse of the cell
provide atp for cellular energy
change shape constantly
carry out reactions using oxygen to break down food
Structure: folded membrane within an outer membrane
The folds of the inner membrane are called cristae
Function: converts energy stored in food into usable energy for work
cellular respiration
mitochondria
contain enzymes that digest non-usable materials within the cell
Contain enzymes produced by ribosomes
Packaged by the Golgi apparatus
Digest worn-out or nonusable materials within the cell
lysosomes
membranous sacs of oxidase enzymes
detoxify harmful susbtances such as alcohol and formaldehyde
break down free radicals (highly reactive chemicals)
replicate by pinching in halves
proxisome
network of protein structures that extend throughout the cytoplasm
provides the cell with an internal framework
cytoskeleton
3 types of cytoskeleton
microfilaments (thinnest)
intermediate filaments
microtubules (largest diameter)
skeleton of our cells; maintains cell shape
cytoskeleton
rod-shaped bodies made of microtubules
direct formation of mitotic spindle during cell division
probably involved in other cell functions that are still not very well known
centrioles
not found in all cells
cilia
flagella
microvilli
move materials across the cell surface
located in the respiratory system to move mucus
cilia
propel the cell
ex. sperm
flagella
tiny, finger-like extensions of the plasma membrane; increase surface area for absorption
microvilli
