Exam 1 Flashcards
Molecule:
A group of atoms held together by bonds
covalent bond:
Single:
Double:
when atoms share electrons, a strong bond is made.
Single Bond: two electrons between 2 atoms
Double Bond: 2 pairs of electrons and 2 pairs of atoms
Ionic Bonds: does it dissolve in water?
forms in the transfer of an electron to another atom–> generated two oppositely charged ions attract each other
yes
Hydrogen Bond:
Important in bonding molecules together–> attraction between polar molecules in which hydrogen is bound to a larger atom, such as oxygen or nitrogen. Hydrogen bonds form an attraction between the positive and negative poles of charged atoms
Solute:
the substance being dissolved (ex: salt) molecule must have a charge (polar, or hydrophilic)
Solvent:
dissolving substance (ex: water)
Rank these terms from smallest to largest: compound, element, molecule, subatomic particle.
element–> Molecule–> compound–> Subatomic Particle
What is the function of a chemical bond? Hypothesize how bonding could be helpful to an organism?
Chemical bonds function are to hold together molecules and create temporary connections essential to life.—> can be used to fuel the bodies activities
Is the hydrogen bond stronger or weaker than covalent and ionic?
hydrogen bonds are weaker than both covalent and ionic compounds — they constantly are breaking and re forming.
What is one example of how hydrogen bonds are used in living things?
Hydrogen bond makes water cohesive, and is what allows certain animals to float on the water. Surface tension
What chemical properties make water polar?
the bent shape- it looks like a v and on one end there is a negitive charge from o2 and a positive charge from the 2 positive hydrogen molecules
How do these chemical properties help plants get water in their leaves? What is this process called?
Cohesion: Hydrogens stick together which allows them to be pulled up through the roots and up into the tree.
Why is water a good solvent?
Water molecules carry a charge- for example when waters negative charge meets that of a positively charged sodium molecule—> ionic bonds holding them together are broken.
Use the terms solute and solvent in a sentence.
A solvent is the liquid that is doing the dissolving. For example, water is a solvent. A solute is the substance that is being dissolved. Something like table salt is an example of a solute.
How are these terms related? Soluble, insoluble, nonpolar, polar, hydrophobic, hydrophilic
they all have to do with things either being able to dissolve, or not dissolve in water
Which property of water helps with heat loss from large bodies of water?
Large heat capacity
high heat capacity
Which subatomic particle determines the bond type?
=
an atoms electrons determine whether and how the atom will bond with other atoms
Lipid:
molecules that include fats, oils and some steroids. – almost all do not dissolve in water
phospholipid
tightly packed lipid molecules that create a layer surrounding the cell. – layer prevents leakage of fluid form cell
hydrophobic
Does not like water
Cell
the most basic unit in any organism, the smallest unit of life. function independently and perform all necessary functions
Plasma membrane
membrane that encompasses the cell
What are phospholipids used for?
Form the membrane that enclose cells.
What is unique about the structure of the phospholipid?
Phospholipids have a polar head, and a non polar tail- creates phospholipid bilayer
Cell
the most basic unit in any organism, the smallest unit of life. function independently and perform all necessary functions
Plasma membrane
membrane that encompasses the cell
cytoplasm
the cells contents within the plasma membrane. fluid inside is called cytosol
eukaryotic
has a nucleus which contains the cells DNA. organisms with eukaryotic cells are called eukaryotes
prokaryotic
has no nucleus- its DNA resides in the cytoplasm. Organisms consisting of prokaryotic cells are called prokaryotes
pili
hair like projection that helps prokaryotes attach to surfaces and acts as a tube to change DNA through
cell wall
Rigid wall that protects and gives shape T cells.
nucleus
Genetic control center, directing most cellular activities– way molecules are produced and in what quantity. – membrane enclosed structure- contains linear strands of DNA
organelle
Specialized structures in Eukaryotes cytoplasm
mitochondria
the organelle in plant and animal cells that concerts energy stored in food into a form of usable by the cell.
diffusion
a particle called a solute is dissolved and moved from an area of HIGH concentration to LOW concenration
simple diffusion
passive transfer– cells that are small and carry no charge (CO2,O2 and water) can directly right through the membrane
facilitated defusion
passive transfer– larger molecules like amino acids and carbohydrates are too big to squeeze through membrane, so they will need a tunnel–>
osmosis
passive transport–the diffusion of water across a cell membrane – water will constantly move with its gradient
hypertonic
solutes outside of cell is higher than the concentration inside the cell, the outside solution is hypertonic.– concentration of solutes outside of cell increases and more water will move out of the cell than into it causing it to shrink.
isotonic
if concentration of solutes outside cell is equal to the solutes inside cell
active transport
Molecules move against their gradient- ATP is required to concentrate the cells together–energy is also needed for the transport of molecules in and out of cell requires energy– ex if ions are being moved against their gradient. – proteins in membrane act as revolving door
bulk transport
plasma membrane absorb large particles and forms a vesicle(requires ATP)
chromatin
long thin fibers consisting of DNA and some proteins- stops DNA from getting tangled
cytoskeleton
internal framework of a cell- role in controlling cell shape, maintaining intracellular organization, and in cell movement.
cilia
small hair like fibers that move fluid along and past the cell
lysosome
round membrane enclosed vesicles that dispose of garbage- filled with digestive enzymes that dissolve macromolecules no longer needed
endoplasmic reticulum
interconnected flattened sacs attached to nuclear membrane– main function is to fold and package proteins for shipment
Golgi apparatus
flattened stack of membranes– process molecules synthesized in the cell– primarily proteins and lipids
vacuole
A membrane-bound vesicle found in the cytoplasm of a cell– function includes intracellular secretion, excretion, storage, and digestion
chloroplast
organelle found in all plants and is the cite of photosynthesis
ribosome
granular dies where proteins are made- scattered throughout cytoplasm
ribosome
bind messenger RNA and transfer RNA to synthesize polypeptides and proteins.
hypotonic
concentration of solutes outside the cell is lower than the concentration inside concentration, the outside solution is hypotonic. – more water molecules will move into the cell with its gradient and the cell will swell
components of nucleus
nuclear membrane- double bilayer – separates nucleus from cytoplasm.
chromatin- long thin fibers consisting of DNA and some proteins- stops DNA from getting tangled
nucleolus- where ribosomes are assembled
Are humans prokaryotic or eukaryotic?
Eukaryotic
What are the roles of the cell membrane?
serves as a checkpoint for what is allowed in and out of the cell— also gives it structure
how phospholipids assembled to form a membrane?
polar heads face outward, polar heat faces inward, leaving the non polar tails to link up creating a non polar layer
What types of molecules are embedded in the membrane?
proteins, carbohydrate, and lipid molecules embedded within or attached
How does the osmosis fit into the discussion of diffusion?
water has its own special way of defusing in and out of the cell. this process is called osmosis – water diffusing
Define passive transport
Passive transport is a movement of ions and other atomic or molecular substances across cell membranes without need of energy input.– unlike active transport which requires energy
bulk transport
The movement of larger macromolecules such as proteins or polysaccharides into or out of the cell is
What are the 4 types of macromolecules?
1) carbohydrates
2) Lipids
3) proteins
4) nucleic acid
What is the difference between simple and complete sugars?
simple sugars consist of macromolecules like glucose and fructose– complex sugars consist of multiple simple sugars combining- could either be a disaccharide or polysacchrides
what are the three optimal pathways for a simple sugar like glucose-
glucose circulate through blood stream
1) used for cellular activity once it enters a cell
2) stored temporarily as glycogen
3) concreted to fat
What roles can complex carbs play in cells?
time release store of energy or as a structural materials for plants
Explain the difference between a saturated and unsaturated fat.
saturated= hydrocarbon chain of fatty acid is bonded to two hydrogen atoms
Unsaturated= when carbon atoms are bonded only to one hydrogen
What role(s) does fat play in cells?
store energy- some is used immediately and others are used later when needed
List the roles that proteins play in living things.
1) structure- hair
2) transport molecules from
3) regulation when being made into hormones
4) enzyme responsible for initiating and assisting every chemical reaction
5) protection- antibodies
6) movement- contract muscles
STREPM
What is the role of the amino acid with regard to proteins?
amino acids rearrange themselves in a unique combination of 20 amino acids– this gives rise to proteins
What is the role of the side chain on an amino acid?
a side chain on an amino acids determines its chemical properties– such as being polar or non polar
form (or shape) determines function. Briefly explain the levels of protein structure in your own words.
Primary Structure: many amino acids bond to create a polypeptide chain
Secondary Structure: hydrogen bonds in the chain causing twist and folding–> into helix and beta plea sheets
Tertiary Structure: Sheets and helixes begin to fold in on themselves
Quaternary Structure: multiple tertiaries proteins connect to create a larger form
Explain how an enzyme can process lactose from milk, so that someone is able to absorb nutrients from milk without getting sick.
enzyme lactase breaks down lactose into two simple sugars that are used for energy
lactose substrate meets with lactase enzyme and splits
What are nucleic acids, such as DNA, made of?
and there 3 components
nucleic acids are made up of individual units called nucleotides
Components:
1) Molecule of sugar
2) Phosphate group
3) Nitrogen containing molecule
What is the role of nucleic acids like DNA and RNA?
DNA: Holds genetic info to bold organisms
RNA: Works as a translator and reads DNA codes–> directs protein production
Both have central roles in directing the production of preteens in living organsims
what is a gene?
physical, and functional unit of heredity. It is because a gene is comprised of nucleotides (on a specific site on a chromosome) that is responsible for the physical and heritable characteristics
what is DNA made of?
Made of 2 strands- both sugar-phosphate-sugar-phosphate- these intertwine turning into a spiral.
base pairs: DNA bases are connected by hydrogen bonds AGCT
What is RNA made of?
DNA sequence is not a direct one and requires help from RNA.
Made from nucleotides, but the sugar group has an extra oxygen atom, and instead of AGCT, is has AGCU
Difference between DNA and RNA
DNA- Double helix -Base pairs AGCT -Holds genetic info to make organisms Has 2 sugar phosphate backbones RNA: Sugar molecule has an extra oxygen -instead of AGCT, it is AGCU -has only one sugar phosphate backbone
Carbohydrate-
primary fuel for cells and form much of the structure of cells in all organisms.
always contain carbon, hydrogen and oxygen.
monosaccharides or simple sugars and the simplest carbohydrate
Macromolecule
Proteins, carbohydrates, nucleic acids, and lipids are the four major classes of macromolecules—large molecules necessary for life that are built from smaller organic molecules
monosaccharide
monosaccharides or simple sugars and the simplest carbohydrate
2 common monosaccharides are fructose and glucose
Disaccharide
from when two simple sugars are bonded together
polysaccharide
forms when a large number of simple sugars are bonded
Triglycerides
fats that have 3 fatty acids linked to the glycerol molecule
What does saturated/unsaturated refer to?
Refers to the hydrocarbon chain of the fatty acids.
Saturated fat
fatty acid chain is bonded with two hydrogen atoms- carries max amount of hydrogen
Unsaturated Fat
Some carbon atoms are bonded to only a single hydrogen atom.
protein
chief building blocks of all life- they help with structure, protection, regulation, contraction, and transportation
enzymes
Enzymes regulate reactions- supply a chemical nudge- without their catalyst, life would not exist.
Amino acids
Macro molecules that store information- two types of nucleic acids– DNA/RNA
Nucleotides
Nucleic acids are made up of individual units called nucleotides. Contains a sugar molecule, a phosphate group, and a nitrogen containing molecule
Potential energy
Stored energy that results from an objects location, position, or composition.
ex: water behind a dam
Kinetic Energy
The energy in motion
ex: legs pushing bike petals.
ATP
(Cellular energy) is a single nucleotide that is highly unstable(bonds in phosphate groups) - creates high energy
when ATP is used– ADP and a free phosphate are produced– energy from the food we eat is used to force phosphate group back on to produce ATP
Thylakoids
location of “photo” reactions, where light is converted into chemical energy.
Pigments
light absorbing molecules
Glycolysis
sequence of chemical reactions taking place in the cytoplasm of the cell- glucose is broken down to form a substance called pyruvate
means the splitting of sugar, that all organisms on the planet take to capture energy
Pyruvate
glucose is broken down to form a substance called pyruvate
Krebs cycle
1) glycolysis- sequence of chemical reactions– glucose is broken down into pyruvates- byproduct of this is ATP NADH and water– codified pyruvate is broken down- CO2 is released into the atmosphere as bonds are broken– energy is captured and used to make two ATP molecules –>NADH
What are the two main locations within a chloroplasts that the reactions of photosynthesis take place in? Identify which is used for the photo reactions and which is used for the synthesis reactions.
In plants, the light reactions take place in the thylakoid membranes of organelles called chloroplasts.
How does photosynthesis relate to cellular respiration
Photosynthesis makes the glucose that is used in cellular respiration to make ATP.
Difference between photosynthesis and cellular respiration
photosynthesis requires carbon dioxide and releases oxygen, cellular respiration requires oxygen and releases carbon
Explain why heat is released every time potential energy is converted to kinetic energy.
in the process of energy transfer, some energy will be lost and this is expelled as heat
Explain how is ATP used for cellular energy in your own words.
The energy created when the ATP phosphate bond is broken can be used to form new chemical bonds and create the organic substances needed by the cell.
What are the general inputs and outputs of photosynthesis? Where do the inputs come “in”? Where do the outputs go “out”?
INPUTS- (1)sunlight (2)water (3)CO2)
1- energy captured from sun
2- water absorbed through roots
3-carbon dioxide absorbed from atmosphere
OUTPUTS- (1) oxygen (2)sugar
stomata
small pores located usually on the underside of leaf- primary site for car exchange in plants– CO2 enters and O2 exits
What are the two main locations within a chloroplasts that the reactions of photosynthesis take place in? Identify which is used for the photo reactions and which is used for the synthesis reactions.
Photosynthesis takes place in organelles called chloroplasts– Make it possible for plants to use sunlight as energy
STROMA- synthesis part of photosynthesis occurs
THYLAKOID- conversion of light energy to chemical energy (photo)
reactions use light energy to make two molecules needed for the next stage of photosynthesis: the energy storage molecule ATP and the reduced electron carrier NADPH.
The photo reactions involve exciting pigments and splitting water. What atoms from the split water molecules are useful for the process of photosynthesis? Which atoms are waste?
a useful byproduct of splitting water molecules is O2 and hydrogen ions
Two parts of Photosynthesis – (photo) and (synthesis)
“photo” part includes concerting light energy into chemical energy–> splitting water molecules and producing O2 and NADP
“synthesis” part is a series of chemical reactions called the Calvin cycle– in tis phase Carbon from CO2 in the atmosphere is attached to molecules in the Stroma- sugars are built
What from the photo reactions are used in the synthesis reactions? How are they used?
ATP and NADPH are later used in the synthesis part–> Calvin cycle uses the energy stored in ATP and NADPH
What is cellular respiration?
process where animals, humans and plants extract energy from high energy bonds if sugars and other energy rich molecules
inputs and outputs of cellular respiration
INPUT- fuel molecules, and oxygen
Outputs- Water, Carbon dioxide and ATP molecules
What is the role of glycolysis in cellular respiration?
glycolysis means splitting sugars, and is the first step in the Kreb cycle – a series of chemical reactions that break down glucose.
What is the role of the Kreb’s citric acid cycle in cellular respiration?
The Kreb cycle is necessary for cellular respiration, because it takes glucose and breaks it down into pyruvetes–> pyruvetes are broken down and there is 3 outcomes
1) new molecule is formed
2) NADH is made and CO2 is released
3) starting material of the Kreb cycle is reformed, ATP is generated and more energy from are created.
What is the role of the Kreb’s citric acid cycle in cellular respiration?
The Kreb cycle is necessary for cellular respiration, because it takes glucose and breaks it down into pyruvetes–> pyruvetes move into mitochondia
Inside mitochondria, hydrogen is removed from pyruvate– this reaction gains 2APT
Electrons are attached electron carries NAD and FAD–> accept electrons from pyruvate–> NAD accepts one and becomes NADH and FAD accepts one becoming FADH2
what is left of the pyruvate is C02 which will escape as gas
Electron carriers deliver their electrons to enzymes carrying oxygen– oxygen is split into two single atoms and then 2 electrons with our food combine with it to make water.
. What is the role of the electron transport chain in cellular respiration?
the electron transport chain creates the largest payoff of energy, as electrons produced in the earlier stages of this cycle(NADH) as the molecules are passed along the chain, energy is released and protons flow into mitochondria. This flow of protons produces ATP.
Anaerobic respiration
first glycolysis - creates 2 pyruvates and 2ATP
Second Krebs- removed electrons from pyruvates– generated electrons 2 APT and co2
electron transfer chain- takes electrons from food, combines them with O2 to create water, which creates ATP. (most payoff)
Anerobic
pyruvates from glycolysis is made into lactic acid- much quicker form of respiration that takes one step–> downside it doesn’t produce enough ATP
Anerobic
pyruvates from glycolysis is made into lactic acid- much quicker form of respiration that takes one step–> downside it doesn’t produce enough ATP
What determine the charge of a molecule
bond types in molecule determine if it has a charge or not
where are proteins made?
genes code for for proteins– begins in the nucleus
