Exam #1 Review Flashcards
What is the definition of metabolism?
total of all the chemical reactions in your body
How many elements are essential to humans?
25
Which elements make up 96% of the weight in the human body?
Oxygen, carbon, hydrogen, nitrogen
What charge do protons have?
Positive
What charge do electrons have?
Negative
What charge do neutrons have?
Neutral
What is the atom’s nucleus made up of?
Protons and neutrons
Where are electrons located in the atom?
They orbit the nucleus
Define atomic number
The number of protons in an atom and gives the atom it’s identity in the periodic table
Where is the atomic number found on the periodic table?
Above the element symbol
Where is the atomic mass found on the periodic table?
Below the element symbol
Define atomic mass
The number of protons plus neutrons
How do you calculate how many neutrons are in an element when looking at the periodic table?
Subtract the atomic mass with the atomic number
Define isotopes
Atoms with the same number of protons but have different number of neutrons
Normal elements that are not isotopes have…
The same number of protons, electrons, and neutrons
When the atomic mass changes we know we are dealing with…
Isotopes
What are the types of chemical bonds?
Ionic bonds, covalent bonds, hydrogen bonds
Defined chemical bonds
Attractions that hold atoms close together
What is an ionic bond?
Attraction between oppositely charged ions
What is an ion?
Adams that are electrically charged as a result of gaining or losing electrons
When an atom loses electrons it becomes _______
Positively charged
When an atom gains an electron it becomes ______
Negatively charged
An easy way to point out an ion is if____
The charge is stated
Na+) or (Cl-
What is a covalent bond?
Attractions that hold items together
Which is stronger a hydrogen bond or a covalent bond?
Covalent bond
If the electrons are shared that means its a _________
Covalent bond
How many electrons are shared in a single covalent bond? And how is this written?
2 electrons
H-H
how many electrons are shared in a double covalent bond? And how is this written?
Four electrons
O=O
What is a hydrogen bond?
Weak attractions by hydrogen atoms
Define polar molecule. And give an example of one
Uneven distribution of charge that creates two poles, one positive pole and one negative pole
Water is a polar molecule containing hydrogen bonds between neighboring water molecules
When an electron is shared in a molecule what kind of bonds are found?
Covalent. Because electrons are shared
Define reactants
The starting materials
Define products
The end materials
How much water are our cells composed of?
70–95%
What are molecules stick together as a result of_____
Hydrogen bonding
What are water special properties?
- It’s cohesion (stickiness)
- Its strong resistance to temperature change
- Ice floats
Water molecules move ______ when forming ice creating a ____ bond
Apart
Stable hydrogen bond (water molecules are far apart)
What is the difference between a solvent and a solute?
A solvent is the dissolving agent (the liquid)
A solute is the dissolved substance (the solid)
Water is the _____ to life
Solvent
Define aqueous solution
When water is the solvent
What is a acid?
A chemical compound that releases H+ into a solution
What happens to hydrogen ions in an acidic solution?
They are taken away
What is the pH scale used for?
To describe the acidity of a solution
The lower pH the more______ a solution is
Acidic
The higher the pH the more _____ a solution is
Basic
What does one need equal parts of in order to have a balanced solution?
Hydrogen ions and hydroxides
There are more______ than _____ in an unbalanced acidic solution
More Hydrogen ions than hydroxides
What is the purpose of a proton?
Determines the element
What is the purpose of a electron?
Participates in forming chemical bonds
What is the purpose of a neutron?
Determines the isotopes
What are the two characteristics of a radioactive isotope?
There is a change in the number of neutrons, it is not stable, it’s atomic mass is different
The ability of an atom to chemically react mostly depends on the number of____
Electrons in the outer electron shell of the atom
Water molecules form hydrogen bonds because
The water molecule is polar
6CO2 + 6 H2O ———> C6H12O6 + 6 O2
In this equation above, what are the reactants?
CO2 and H2O
Define organic compound and one characteristic of them
Carbon-based molecules
Contains a carbon carbon backbone
Define functional groups
The group of atoms in organic compounds involved in chemical reactions
What is the difference between a single in a double bond?
In a single bond only one pair of electrons is shared
In a double bond two pairs of electrons are shared
What are macromolecules?
Very large molecules
What are types of macromolecules?
Carbohydrates, proteins, nucleic acid
Define monomer
A molecule that can be bonded to other identical molecules in order to form a polymer
Essentially building blocks
What is a polymer made up of
Identical monomers
A dehydration reaction involves…
The removal of water through a building reaction
Dehydration reaction helps link monomers together to make a polymer by…
Removing a molecule of water between the monomers
What does a hydrolysis reaction consist of?
Breaking a bond by taking apart polymers turning them back into monomers through adding a molecule of water between the monomers
Digestion is a form of a _______reaction
Hydrolysis
Why/when would we want to break down macromolecules?
We need to digest macromolecules to make their monomers available to our cells
Define carbohydrates
Includes sugars and polymers of sugars
What is the monomer for carbohydrates?
Monosaccharide
In animals carbohydrates are a primary source of_______
Dietary energy
What are some examples of monosaccharides?
Glucose fructose and galactose
What are isomers? Give two examples…
Molecules that have the same molecular formula but different structures
Glucose and fructose
What is the chemical formula for glucose?
C6H12O6
What is a disaccharide? And what is essential to form it?
Two monosaccharides linked together by a dehydrated reaction
Carbon carbon backbone is essential
What are some examples of disaccharides?
Sucrose Maltos and lactose
Define polysaccharides
Long chains of sugar polymers of monosaccharides
Polysaccharides also means many sugars
Give three examples of polysaccharides
Starch Glaswegian and cellulose
Where is glycogen stored?
In liver and muscle cells
What is a plant cell wall made up of?
Cellulose
What is one polysaccharide that humans cannot break down?
Cellulose
What is cellulose made up of?
Many linked glucose monomers
What is the difference between hydrophilic and hydrophobic?
Hydrophilic means water loving
Hydrophobic means water fearing
What substance is hydrophilic?
What substance is hydrophobic?
Carbohydrates
Lipids
What makes lipids special?
Lipids are made up of different molecular building blocks
They are not macromolecules bc it does not have monomers or identical links
Yet they are organic compounds because they have the carbon carbon backbone
What is a necessary characteristic of a organic compound?
A carbon carbon backbone
What are some essential functions fat performs in the human body?
Energy storage, cushioning, insulation
When looking at a carbon skeleton of a fatty acid chain we know that it is a macromolecule or not based off of what fact?
Wether there are monomers or not (identical sets)
When looking at a carbon skeleton of a fatty acid with three chains branding off the head, how many need to be unsaturated for it to be considered unsaturated?
One
How do you point out an unsaturated lipid within a carbon skeleton of a fatty acid chain?
There will be a double bond
CH2-CH=OI-CH2
How do you know if the carbon skeleton of a fatty acid link is saturated?
There will be ONLY single bonds
CH2-CH2-CH2
A saturated fat. has all three of its fatty acids______
Saturated
How many links does carbon need to have in a fatty acid?
four links
C-CH2-CH
| | |
1 2 1
What is a main physical difference of saturated and unsaturated fats?
Saturated fats are liquid
unsaturated fats are solids
What is hydrogenation?
Converts unsaturated fats to saturated fats by adding hydrogen
What are the major types of proteins and their uses?
- Structural proteins -provide support
- Storage proteins- provide amino acids for growth
- Contractile proteins- help movement (muscles)
- Transport proteins- help transport substances
- Enzymes - help chemical reactions
What are amino acids?
Monomers (building blocks) to proteins
How do amino acids form proteins?
By linking together in a bead manor then twisting and coiling together to create a ball of protein
What are three structural aspects to make an amino acid?
Carboxyl, amino, hydrogen
What is a peptide bond?
Bonds that join amino acids by dehydration reactions!
In what shape is protein functional?
In 3-D ball
What are polypeptides?
Long chains of amino acids
the stage before the roiling up
Does the shape of a protein matter?
Yes, the structure of the protein enables its functions
What are ways to alter a proteins function/shape?
Mutation (by one abnormal amino acid), temperature, and PH level
What are the monomers of carbs?
Monosaccharides
*RNA contains a copy of _____
DNA
A specific sequence of DNA is called a _____
Gene
What do nucleic acids do?
Store information, and provide instructions for building proteins
*What makes up a nucleotide?
Sugar, phosphate, and base
What are the two types of nucleic acids?
RNA and DNA
*What are chromosomes made up of?
DNA
What are the monomers (building blocks) of nucleic acids?
Nucleotides
what are the three parts of each nucleotide?
- Five carbon sugar
- Phosphate groups
- Nitrogen-containing base
What is an important element to a nucleotide?
A sugar-phosphate backbone
What differentiates each nucleotide?
Its base
What are the four possible bases for nucleotides?
Adenine,
Guanine,
Thymine,
Cystosine
What is the ‘base pairing rule’?
A only pairs with T
G only pairs with C
If one DNA strands has the sequence ACTGGT, what is the sequence of the other strand?
TGACCA
*What are three major difference between RNA and DNA?
- The RNA sugar is ribose and the DNA sugar is deoxyribose
- RNA’s base is uracil (u) (no T base!)
- RNA is found in a single stand, DNA is found in a double strand
What are the three domains biologists classify all of life into? And what type of cells are they each?
Bacteria -Prokaryotic cell
Archaea- Prokaryotic cell
Eukarya- Eukaryotic cell
*What are the main difference of a prokaryotic cell and a eukaryotic cell? And which is larger?
A prokaryotic cell is smaller and has no membrane bound organelles
A eukaryotic cell is larger and has membrane bound organelles (a nucleus!)
What do chromosomes do?
Carry genes made up of DNA
*What is the plasma membrane? And what is it made up of?
Barrier between the inside and outside of the cell (boundary/boarder of cell)
made up of phospholipids
What do ribosomes do?
Synthesize (make) proteins
What are phospholipids?
Main component of plasma membrane or cell membrane
*What are the parts of a phospholipid and its characteristics? and how are they arranged
Phospholipid has a head and a tail.
The head is hydrophilic so it faces the cytoplasm inside the cell, and the tail is hydrophobic.
Phospholipids are arranged into a two-layer sheet
Where are hydrophilic amino acids in a cell?
On the top and bottom of the cell facing the cytoplasm
What does peptidoglycan refer to?
The cell wall of prokaryotic cells
What do flagella do?
Move prokaryotic cell though liquid
a propeller
*What is chloroplast?
Sight of photosynthesis, green in color
What type cells are plant and animal cells?
Eukaryotic
What are three characteristics of plant cells?
Contains:
chloroplast,
cell wall surrounding cell membrane,
central vacuole (helps with water pressure in cell)
What are two characteristics of animal cells?
Contains:
centrosomes (for mitosis)
lysosomes
Ribosomes are found in both ____ and ____ cells.
Eukaryotic and prokaryotic
What do ribosomes do?
Make proteins
How do ribosomes make proteins?
By collecting data from mRNA translating its message to a protein
Where are ribosomes made?
In the nucleus
How is a protein made
DNA copies half itself to make an mRNA in order to deduce its size.
mRNA travels out of nucleus through nuclear pore into cytoplasm
in the cytoplasm mRNA binds to a ribosome
DNA–> mRNA–>Protein
Which cell contains DNA and which cell contains ribosomes, a prokaryotic cell or a eukaryotic cell?
They both contain both DNA and ribosomes
Which organisms contain a prokaryotic cell?
Bacteria and archaea
Which organisms contain a eukaryotic cell?
Animals
Plants
Fungi
Protists
Which cell contains a nucleus a prokaryotic cell or a eukaryotic cell? Which contain a membrane-bound organelle?
A eukaryotic cell contains a membrane-bound organelle (an example of this is a nucleus)
What are the three most common shapes of prokaryotes?
- Cocci =spherical
- Bacilli=rod-shaped
- Spirochetes=spiral or curved
What are the two classifications of bacteria?
Gram-positive bacteria- thick peptidoglycan layer, looks purple after staining
Gram-negative bacteria- thin peptidoglycan layer, looks pink after staining (bc can retain the color due to such a thin outer layer)
What are two ways in which bacteria can eat?
Autotrophs- “self feeders” make their own food ( plants self feed through sunlight through photosynthesis)
Heterotrophs- “other feeders” rely on others living organisms to provide the with food (we are heterotrophs)
