BIO 230 LATEST 2026 CORE EXAM SET QUESTIONS AND
ANSWERS RATED A+
✔✔chromosomes become visible as - ✔✔eukaryotic cells prepare to divide
✔✔__ were discovered in the 19th century as threadlike structures in the nucleus of
eukaryotic cells that become visible as the cells begin to divide - ✔✔chromosomes
✔✔we now know that the __ carries the genetic information of the cell and that protein
components of __ function largely to package and control the enormously long dna
molecules - ✔✔dna
chromsomes
✔✔a long polymer composed of only four types of nucleotide subunits, which are
chemically very similar to one another - ✔✔dna
✔✔early in the 1950s, Maurice Wilkins and Rosalind Franklin examined dna using __
__ __ __, a technique for determining the three dimensional atomic structure of a
molecule. their results provided one of the crucial pieces of evidence that led to watson
and cricks model of the double helical structure of dna. this structure immediately
suggested how dna could encode the instructions necessary for life and how these
instructions could be copied and passed along when cells divide - ✔✔x ray diffraction
analysis
✔✔a dna molecule consists of - ✔✔two complementary chains of nucleotides
✔✔a molecule of __ consists of two long polynucleotide chains. each chain or strand is
composed of four types of nucleotide subunits, and the two strands are held together by
__ __ between the base portions of the nucleotides - ✔✔dna
hydrogen bonds
✔✔dna is made of __ nucleotide building blocks. each nucleotide is composed of a __
__ covalently linked to a __. the nucleotides are covalently linked together into
polynucleotide chains, with a __-__ __ from which the bases-adenine, cytosine,
guanine, and thymine extend. - ✔✔4
sugar phosphate
base
sugar phosphate backbone
✔✔the nucleotide subunits within a dna strand are held together by -
✔✔phosphodiester bonds
✔✔for the nucleotides in dna, the sugar is __ and the base can either be __, __, __, or
__. the nucleotides are covalently linked together in a chain through the sugars and
,phosphates, which form a backbone of alternating sugar phosphate sugar phosphate.
because only the base differs in each of the four types of subunits, each polynucleotide
chain resembles a __: a sugar phosphate backbone strung with four types of tiny beads
- ✔✔deoxyribose
adenine
cytosine
guanine
thymine
necklace
✔✔because the ester linkages to the sugar molecules on either side of the bond are
different, each dna strand has a - ✔✔chemical polarity
✔✔the two polynucleotide chains in the dna double helix are held together by __ __
between the bases on the different strands. all the bases are therefore on the inside of
the double helix, with the sugar phosphate backbones on the outside - ✔✔hydrogen
bonding
✔✔__ always pairs with __ and __ always pairs with __ .in each case, a bulkier two ring
base is paired with a single ring base. each purine-pyrimidine base is called a __ __,
and this __ __-__ enables the base pairs to be packed in the energetically most
favorable arrangement along the interior of the double helix - ✔✔a
t
g
c
base pair
complementary base pairing
✔✔the antiparallel sugar phosphate strands then twist around each other to form a __
__ containing __ base pairs per helical turn. this twisting also contributes to the
energetically favorable conformation of the dna double helix - ✔✔double helix
10
✔✔the two strands of the dna double helix are held together by __ __ between
complementary base pairs - ✔✔hydrogen bonds
✔✔a __ __ __ shows the conformation of the dna double helix. the two dna strands
wind around each other to form a __ __ __. the wider groove is called the __ __ and the
smaller one the __ __ - ✔✔space filling model
right handed helix
major groove
minor groove
,✔✔each strand of a dna double helix contains a sequence of nucleotides that is exactly
__ to the nucleotide sequence of its partner strand- an __ always matches a __ on the
opposite strand, and a __ always matches a __ - ✔✔complementary
a
t
c
g
✔✔the structure of dna provides a mechanism for - ✔✔heredity
✔✔organisms differ from one another because their respective dna molecules have
different __ __ and consequently carry different biological messages - ✔✔nucleotide
sequences
✔✔the function of a protein is determined by its __ __ __, which in turn is determined by
the sequence of the Amino acids in its polypeptide chain - ✔✔three dimensional
structure
✔✔the process by which the nucleotide sequence of a gene is transcribed into the
nucleotide sequence of an RNA molecule, and then, in most cases, translated into the
amino acid sequence of a protein - ✔✔gene expression
✔✔most genes contain information to make - ✔✔proteins
✔✔each human cell contain about __ meters of dna; yet the cell nucleus is only __-__
um in diameter - ✔✔2
5-8
✔✔in eukaryotic cells, very long double stranded dna molecules are packaged into __.
these not only fit handily inside the nucleus, but , after they are duplicated, they can be
accurately appointed between the two daughter cells at each cell division -
✔✔chromsomes
✔✔__ typically carry their genes on a single, circular dna molecule - ✔✔bacteria
✔✔eukaryotic dna is packaged into - ✔✔multiple chromosomes
✔✔the dna in a human nucleus for example is parceled out into 23 or 24 different types
of chromosome, depending on an individuals sex. each of these chromosomes consists
of a single, enormously long, linear dna molecule associated with proteins that fold and
pack the fine thread of dna into a more compact structure. this complex of dna and
protein is called - ✔✔chromatin
, ✔✔with the exception of the gametes and highly specialized cells that lack dna entirely,
human cells each contain two copies of every chromsome, one inherited from the
mother and one from the father. the maternal and paternal versions of each
chromosome are called __ __. - ✔✔homologous chromosomes
✔✔the only non homologous chromosome pairs in humans are the - ✔✔sex
chromosomes in males
✔✔each full set of human chromosomes contains a total of approx. 3.2 times 10^9
nucleotide pairs of dna- which together comprise the - ✔✔human genome
✔✔in addition to being different sizes, the different human chromosomes can be
distinguished from one another by a variety of techniques. each chromosome can be __
a different color using sets of chromosome specific dna molecules coupled to different
fluorescent dyes. an earlier and more traditional way of distinguishing one chromosome
from another involves __ them with __ - ✔✔painted
staining
dyes
✔✔an ordered display of the full set of 46 human chromosomes is called the -
✔✔human karyotype
✔✔the most important function of chromosomes is to - ✔✔carry genes
✔✔a __ is often defined as a segment of dna that contains the instructions for making a
particular protein or rna molecule - ✔✔gene
✔✔in __, genes are closely packed along chromosomes - ✔✔yeast
✔✔the __ __ genome contains about 12.5 million nucleotide pairs and 6600 genes -
✔✔s cerevisiae
✔✔together, the total genetic information carried by a complete set of the chromosomes
present in a cell or organisms constitutes its - ✔✔genome
✔✔__ and some __ __ __, including __ __, have especially compact genomes: the dna
molecules that make up their chromosomes are little more than strings of closely
packed genes. however, chromosomes from many eukaryotes contain, in addition to
genes and the specific nucleotide sequences required for normal gene expression, a
large excess of interspersed dna. this extra dna is sometimes erroneously called __ __
because its usefulness to the cell has not yet been demonstrated - ✔✔bacteria
single celled eukaryotes
budding yeast
ANSWERS RATED A+
✔✔chromosomes become visible as - ✔✔eukaryotic cells prepare to divide
✔✔__ were discovered in the 19th century as threadlike structures in the nucleus of
eukaryotic cells that become visible as the cells begin to divide - ✔✔chromosomes
✔✔we now know that the __ carries the genetic information of the cell and that protein
components of __ function largely to package and control the enormously long dna
molecules - ✔✔dna
chromsomes
✔✔a long polymer composed of only four types of nucleotide subunits, which are
chemically very similar to one another - ✔✔dna
✔✔early in the 1950s, Maurice Wilkins and Rosalind Franklin examined dna using __
__ __ __, a technique for determining the three dimensional atomic structure of a
molecule. their results provided one of the crucial pieces of evidence that led to watson
and cricks model of the double helical structure of dna. this structure immediately
suggested how dna could encode the instructions necessary for life and how these
instructions could be copied and passed along when cells divide - ✔✔x ray diffraction
analysis
✔✔a dna molecule consists of - ✔✔two complementary chains of nucleotides
✔✔a molecule of __ consists of two long polynucleotide chains. each chain or strand is
composed of four types of nucleotide subunits, and the two strands are held together by
__ __ between the base portions of the nucleotides - ✔✔dna
hydrogen bonds
✔✔dna is made of __ nucleotide building blocks. each nucleotide is composed of a __
__ covalently linked to a __. the nucleotides are covalently linked together into
polynucleotide chains, with a __-__ __ from which the bases-adenine, cytosine,
guanine, and thymine extend. - ✔✔4
sugar phosphate
base
sugar phosphate backbone
✔✔the nucleotide subunits within a dna strand are held together by -
✔✔phosphodiester bonds
✔✔for the nucleotides in dna, the sugar is __ and the base can either be __, __, __, or
__. the nucleotides are covalently linked together in a chain through the sugars and
,phosphates, which form a backbone of alternating sugar phosphate sugar phosphate.
because only the base differs in each of the four types of subunits, each polynucleotide
chain resembles a __: a sugar phosphate backbone strung with four types of tiny beads
- ✔✔deoxyribose
adenine
cytosine
guanine
thymine
necklace
✔✔because the ester linkages to the sugar molecules on either side of the bond are
different, each dna strand has a - ✔✔chemical polarity
✔✔the two polynucleotide chains in the dna double helix are held together by __ __
between the bases on the different strands. all the bases are therefore on the inside of
the double helix, with the sugar phosphate backbones on the outside - ✔✔hydrogen
bonding
✔✔__ always pairs with __ and __ always pairs with __ .in each case, a bulkier two ring
base is paired with a single ring base. each purine-pyrimidine base is called a __ __,
and this __ __-__ enables the base pairs to be packed in the energetically most
favorable arrangement along the interior of the double helix - ✔✔a
t
g
c
base pair
complementary base pairing
✔✔the antiparallel sugar phosphate strands then twist around each other to form a __
__ containing __ base pairs per helical turn. this twisting also contributes to the
energetically favorable conformation of the dna double helix - ✔✔double helix
10
✔✔the two strands of the dna double helix are held together by __ __ between
complementary base pairs - ✔✔hydrogen bonds
✔✔a __ __ __ shows the conformation of the dna double helix. the two dna strands
wind around each other to form a __ __ __. the wider groove is called the __ __ and the
smaller one the __ __ - ✔✔space filling model
right handed helix
major groove
minor groove
,✔✔each strand of a dna double helix contains a sequence of nucleotides that is exactly
__ to the nucleotide sequence of its partner strand- an __ always matches a __ on the
opposite strand, and a __ always matches a __ - ✔✔complementary
a
t
c
g
✔✔the structure of dna provides a mechanism for - ✔✔heredity
✔✔organisms differ from one another because their respective dna molecules have
different __ __ and consequently carry different biological messages - ✔✔nucleotide
sequences
✔✔the function of a protein is determined by its __ __ __, which in turn is determined by
the sequence of the Amino acids in its polypeptide chain - ✔✔three dimensional
structure
✔✔the process by which the nucleotide sequence of a gene is transcribed into the
nucleotide sequence of an RNA molecule, and then, in most cases, translated into the
amino acid sequence of a protein - ✔✔gene expression
✔✔most genes contain information to make - ✔✔proteins
✔✔each human cell contain about __ meters of dna; yet the cell nucleus is only __-__
um in diameter - ✔✔2
5-8
✔✔in eukaryotic cells, very long double stranded dna molecules are packaged into __.
these not only fit handily inside the nucleus, but , after they are duplicated, they can be
accurately appointed between the two daughter cells at each cell division -
✔✔chromsomes
✔✔__ typically carry their genes on a single, circular dna molecule - ✔✔bacteria
✔✔eukaryotic dna is packaged into - ✔✔multiple chromosomes
✔✔the dna in a human nucleus for example is parceled out into 23 or 24 different types
of chromosome, depending on an individuals sex. each of these chromosomes consists
of a single, enormously long, linear dna molecule associated with proteins that fold and
pack the fine thread of dna into a more compact structure. this complex of dna and
protein is called - ✔✔chromatin
, ✔✔with the exception of the gametes and highly specialized cells that lack dna entirely,
human cells each contain two copies of every chromsome, one inherited from the
mother and one from the father. the maternal and paternal versions of each
chromosome are called __ __. - ✔✔homologous chromosomes
✔✔the only non homologous chromosome pairs in humans are the - ✔✔sex
chromosomes in males
✔✔each full set of human chromosomes contains a total of approx. 3.2 times 10^9
nucleotide pairs of dna- which together comprise the - ✔✔human genome
✔✔in addition to being different sizes, the different human chromosomes can be
distinguished from one another by a variety of techniques. each chromosome can be __
a different color using sets of chromosome specific dna molecules coupled to different
fluorescent dyes. an earlier and more traditional way of distinguishing one chromosome
from another involves __ them with __ - ✔✔painted
staining
dyes
✔✔an ordered display of the full set of 46 human chromosomes is called the -
✔✔human karyotype
✔✔the most important function of chromosomes is to - ✔✔carry genes
✔✔a __ is often defined as a segment of dna that contains the instructions for making a
particular protein or rna molecule - ✔✔gene
✔✔in __, genes are closely packed along chromosomes - ✔✔yeast
✔✔the __ __ genome contains about 12.5 million nucleotide pairs and 6600 genes -
✔✔s cerevisiae
✔✔together, the total genetic information carried by a complete set of the chromosomes
present in a cell or organisms constitutes its - ✔✔genome
✔✔__ and some __ __ __, including __ __, have especially compact genomes: the dna
molecules that make up their chromosomes are little more than strings of closely
packed genes. however, chromosomes from many eukaryotes contain, in addition to
genes and the specific nucleotide sequences required for normal gene expression, a
large excess of interspersed dna. this extra dna is sometimes erroneously called __ __
because its usefulness to the cell has not yet been demonstrated - ✔✔bacteria
single celled eukaryotes
budding yeast
