Bio 101 Final

What is the difference between free and attached ribosomes?

-Free ribosomes are in the cytoplams while attached ribosomes are anchored to the endoplasmic reticulum
-Free ribosomes produce proteins that remain in the cytosol while attached ribosomes produce proteins that may be exported from the cell

Fibers of the cytoskeleton are composed of primarily of

proteins

The last step in the synthesis of secretory protein synthesis is

exocytosis

DNA is located in which of the following?

-chloroplasts
-animal cells
-plant cells
-prokaryotic cells

Researchers have been able to study the pathway of a secreted protein by tagging it with a florescent marker. Using this method, you would observe florescents moving from the ER to which organelle?

Golgi complex

Which of the following does not possess a double membrane?

Ribosome

What cell component is made of both RNA and proteins and is found as large and small subunits in the cytoplasm?

Ribosomes

What is a codon?

a base sequence of mRNA that codes for a specific amino acid

Which molecule is synthesized in transcription, exits the nucleus, and has information in the from of codons?

mRNA

Which of the following is the best description of a gene?

a segment of DNA that is transcribed into a mRNA, a tRNA, and a rRNA

In a typical animal cell, the cell cycle phase that is longest is?

G1

If a cell contains 20 chromosomes, how many chromatids will be present during prophase?

40

Human body cell nuclei contain ____ pairs of chromosomes.

23

During the "s" portion of interphase, what is the cell doing?

sythensizing DNA

Imagine that a species has 8 chromosomes (4 homologous pairs). If some event occurred that prevented meiosis from occurring after replication, how many chromosomes would the species have after 2 generations?

32

If a eukaryotic cell has 20 chromosomes and it undergoes meiosis, how many cells will result, and how many chromosomes will they contain?

4 cells; 10 chromosomes each

What is one of the ways mitosis and meiosis are different?

There are 2 chromosome divisions in meiosis and only 1 in mitosis

What is the term for 2 chromosomes that have the same length, shape, and genes, but do not have exactly the same DNA sequence?

Homologous chromosomes

The main determiner of male sex in humans is

The presence of the y chromosome

When a fragment breaks from a chromosome and rejoins it, in a flipped orientation, the result is called a/an:

inversion

Which of the following is not a known function of the cytoskeleton?

to maintain a critical limit on cell size

The cytoplasm of eukaryotic cells contains

water, dissolved nutrients, organelles, enzymes

Lysosomes:

-help to digest worn out or damaged organelles
-fuse with food vacuoles to expose nutrients to lysosomal enzymes
-recycle materials within the cell
-destroy harmful bacteria engulfed by white blood cells

The golgi packages materials into ______ for transport or export.

vesicles

If a DNA sequence has the sequence GCTAA what RNA sequence will be made from it?

CGAUU

Which cell structure is not part of translation?

operon

______ are to proteins as nucleoties are to DNA.

amino acids

During S phase, chromosomes are converted to what form?

sister chromatids

Normal cell operations and growth occur during the gap period called

G1

The longest period of a cell's life cycle is

interphase

What would be the result of an error in anaphase that failed to separate a pair of sister chromatids?

1 cell would have an extra chromosome and 1 cell would lack a chromosome

The products of meiosis are

4 genetically different haploid cells

What event occurs in both anaphase of mitosis and anaphase II of meiosis II?

sister chromatids separate

What important event is associated with anaphase I of meiosis I?

homologous chromosomes are separated

What makes the Y chromosome unusual?

it has very few genes

A recessive gene that is on a human X chromosome

is more likely to be expressed by males

House ammonia has a pH of 12; household bleach has a pH of 13. Which of the following statements is true?

The ammonia has 10 times as many H+ ions as the bleach.

A compound contains

2 or more elements in a fixed ratio

______ often forms as a result of polar bonds.

Hydrogen bonds

How does one explain the formation of ions?

gain or loss of electrons

Carbon is able to form an immense diversity of organic molecules because of carbon's

-ability to bond with up to four other atoms
-capacity to form single and double bonds
-tendency to form covalent bonds
-ability to bond together to form extensive, branched, or unbranched carbon skeletons

The formation of large, repetitive organic molecues form small monomers is a/an reaction.

Condensation (dehydration synthesis)

Peptide bonds

link amino acids

Organisms contain thousands of different proteins composed of ________ different amino acids.

20

The BEST description of a coupled reaction is

two reactions that involve one providing energy for the other

Why is it possible for living organisms to comply with the second law of thermodynamics?

Sunlight functions as an ultimate source of energy for most forms of life on earth

Which of the following is not endergonic?

-NOT bonding sugars together to form glycogen
-NOT adding a phosphate group to ADP to form ATP
-NOT bonding amino acids together to form proteins
-NOT bonding fatty acids and glycerol together to form lipids
(All answers are endergonic)

Energy present in a system that is not usable to do work relates to the system's:

Entropy

The diversity of chemical reactions occurring in a cell depends mostly on certain molecules present in the cells, which are called:

enzymes

Why are enzymes important?

because they allow reactions to occur at body temperature

All of the statements pertaining to catalysts are true except:

catalysts increase activation energy requirements

End products of biosynthetic pathways often act to block the initial step in that pathway. This phenomenon is called

feedback inhibition

A "high energy" bond in ATP molecule is located between

two phosphate groups

What activates ATP synthase to produce ATP?

H+ ions flowing across the mitochondrial inner membrane

The Krebs Cycle is carried out during

aerobic respiration

The products of the Krebs Cycle include:

CO2

Energy Carriers

ATP

The formation of sodium chloride (NaCl) is the result of

attraction between opposite charges

covalent bonding

Which of the following is not related to the ability of NaCl to dissolve into water?

Hydrogen bonds between water molecules are weaker than the hydrogen bonds between sodium and water or between chloride and water.

Bases _____.

either accept H+ ions form solutions or donate OH+ ions to solutions

Which of the following statements about pH is true?

An increase in hydrogen ion concentration means a decrease in pH scale units

What type of chemical reaction results in the breakdown of organic polymers into their respective subunits?

hydrolysis

Nucleotides are the building blocks for

ATP, NAD, and FAD

Glucose molecules are to starch as ________ are to proteins.

amino acids

Which list below consists of only polymers?

proteins, lipids, nucleic acids, polysaccharides

The second law of thermodynamics states that

in energy-yielding reactions, matter goes from a more-ordered to a less-ordered state.

The first law of dynamics states that

energy can neither be created or destroyed

Energy is a measure of

increase in randomness

During photosynthesis, plants convert light energy to chemical energy. This is an illistration of

the first law of thermodynamics

Place the steps of enzyme catalysis in the correct order:

1. Substrate and enzyme change shape

2. Substrate enters the active site

3. Enzyme reverts to original configuration

4. Product is expelled

2, 1, 4, 3

Enzymes are made up of

amino acids

The reactant is an enzyme catalyzed reaction is the

substrate

Calcium has an atomic number of 20. A Calcium ion could have

18 electrons

The element carbon has an atomic number of six. Carbon would most likely

form 4 covalent bonds

Compared to a solution of pH 3, a solution of pH 1 is

100x more acidic

In the equation 2H2+O2 -->2H2O

only H2O is a compound.

A protein containing more than one polypeptide chain exhibits the ________ level of protein structure.

Quaternary

Which of the following is an amino group?

NH2

Which of the following statements is/are true about dehydration synthesis?

-H2O is formed as the monomers are joined

-1 Monomer loses a Hydrogen atom and the other loses a hydroxyl group

-Covalent bonds are formed between the monomers

-Electrons are shared between atoms of the joined monomers

Which of the following is true about energy?

-it can be stored in chemical bonds

-it can be released by breaking chemical bonds

Which of the following reactions are endergonic?

-making starch from many glucose molecules

-making proteins from many amino acids

-making many glucose molecules from many glycogen molecules

Which of the following reactions would have products with more energy than the substrates?

adding a phosphate group to ADP to form ATP

Which of the following functions as a biological catalyst?

enzyme

Which of the following is an example of lowering activation energy?

lowering the energy required to start a chemical reaction

You have been given the job of researching for naturally occurring catalysts. All of the following have been isolated from the environment. Which of the following would be an example of a catalyst?

A protein converting glucose and fructose into sucrose without being changed itself

The optimum reaction rate of a particular enzyme occurs at pH 7.3 at 37 degrees Celcius. This reaction would probably cure faster by

increasing the temp to 39 degrees and keeping the pH at 7.3

Which of the following is not a common energy carrier in the cell?

Phosphate

The term anaerobic means

without O2

In the ETC, the final electron acceptor is

an oxygen atom