TEAS 6 SCIENCE- LIFE + PHYSICAL SCIENCES QUESTIONS WITH COMPLETE SOLUTIONS
Name the 4 basic organic macromolecules. What are they produced by? - ANS:
... [Show More] 1. carbohydrates
2. lipids
3. proteins
4. nucleic acids
*produced by anabolic reactions
Name the 4 basic building blocks. What type of reactions are they involved in? - ANS: 1. monosaccharides (glucose) for cabohydrates
2. amino acids for protein
3. fatty acids (glycerol) for lipids
4. nucleotides for nucleic acids
*catabolic reactions
What is an anabolic reaction? - ANS: builds large and complex molecules from smaller ones
*requires energy
What is a catabolic reaction? - ANS: larger molecules are broken down into smaller ones
*releases energy
Dfferentiate between endothermic and exothermic reactions - ANS: 1. endothermic: absorbs heat
2. exothermic: releases heat
What is the primary source of energy? Why? - ANS: 1. carbohydrates
2. can be easily converted into glucose
What are carbohydrates broken down into? - ANS: simple sugars/glucose
What are the groupings of simple sugars? - ANS: 1. monosaccharide: 1 monomer of sugar
-glucose, fructose, and sucrose
2. disaccharide: 2 monomers of sugar
What type of bonds do lipids have? Are they hydrophobic or hydrophilic? - ANS: 1. C-H
2. hydrophobic b/c of fatty acid tails
What are 3 types of lipids? - ANS: 1. phospholipids
2. steroids
3. waxes
Describe triglycerides, phospholipids, steroids, and waxes - ANS: 1. triglycerides: contains a glycerol head + 3 fatty acids
2. phospholipids: contains a phosphate head + 2 fatty acids
-aids in cell structure and membrane
3. steroids: are derived from cholesterol, which is found in the cell membrane and throughout the blood
4. waxes: a long chain alcohol binds to a long chain fatty acid
What are polypeptides? Why does it occur? - ANS: 1. a linkage of multiple (10-100) peptides; an amino acid chain
2. is a result of condensation reactions
Differentiate between condensation reactions and hydrolysis. - ANS: 1. condensation reactions: removal/loss of water when 2 molecules are joined together
2. hydrolysis: addition of water; water is broken down into H+ cations and OH- anions
What is a peptide? - ANS: a compound of 2 or more amino acids
What makes up an amino acid? - ANS: 1. amino group (NH2)
2. carboxyl group (COOH)
3. R group (determines properties of protein)
4. hydrogen
5. carbon
Describe the 4 protein structures - ANS: 1. primary: a sequence of amino acids
2. secondary: double helix and beta plated sheets stabilized by hydrogen bonds
3. tertiary: overall shape of protein molecule
4. quarternary: multiple protein molecules linked together
Describe these protein functions: structural, enzymes, receptors, Antibodies, motor proteins, pump proteins, switch proteins - ANS: 1. structural: gives stiffness + rigidity to components that would be fluid (ex: keratin gives rigidity to nails and hair)
2. enzymes: catalyzes chemical rxns.
3. receptors: binds a signaling molecule to raise a response
4. Antibodies./immunoglobulins: binds to antigens and targets them for destruction
5. motor proteins: forces responsible for muscle contractions
6. pump proteins: transports ions/small molecules across membrane
7. switch proteins: turns on or off based off the presence or absence of another molecule in the cell
What is the function of enzymes? - ANS: make reactions occur faster and more often
*DOES NOT start chemical rxns.
Why do enzymes deal with the substrates? What are substrates? - ANS: 1. because they bind to the active site of the enzyme to speed up an reaction
2. reactants that have a specific shape that binds to the active site of a enzyme containing the same shape
What are nucleotides joined by? - ANS: phosphodiester bonds
What is nitrogen fixation? - ANS: used to synthesize nucleotides for DNA and amino acids for proteins
RNA catalyzes DNA genetic info into what? - ANS: protein coded information
What are nucleotides made up of? - ANS: 1. 5 carbon sugar
-deoxyribose
-ribose
2. nitrogenous base
-purines: adenine + guanine
-pyrimadines: cytosine, uracil, thymine
3. phosphate group
Describe the nucleic acids for RNA and DNA - ANS: 1. RNA: ribose, adenine, guanine, cytosine, uracil
-single stranded
2. DNA: deoxyribose, adenine, guanine, cytosine, thymine
-single or double stranded
What type of genetic information does organisms and viruses carry? - ANS: 1. Organisms: DNA
2. Viruses: most carry DNA but some may carry RNA
Each base pair of DNA (A, G, C, T) attaches to what to form a nucleotide? ` - ANS: a phosphate group and sugar molecule
What shape does nucleotides form? - ANS: double helix
*act as a rung on a ladder
How are nitrogenous bases attached to one another ? - ANS: with hydrogen bonds; allows for easy dismantle to replicate
How can DNA replicate itself? - ANS: by splitting base pairs apart in a double helix
-each new cell must/needs to contain an exact copy of DNA from an old cell
Differentiate b/w purines and pyrimidines - ANS: 1. pyrimidines: C, U, T
-6 sided
-single ring shape
2. purines: A, G
-2 attached rings
-one has 5 sides while the other has 6
What are codons? - ANS: - a group of 3 nucleotides on mRNA
-contains the code for a single amino acid
How many codons are there in the body? How many amino acids are in the body? - ANS: 1. 64
2. 20 [Show Less]