Final Exam Multiple Choice Practice_BIO 111 LN

To add phosphate groups onto proteins

What is the function of a protein kinase?

They are lipid-soluble

What property defines most ligands for intracellular receptors?

signal amplification.

A small number of cell surface receptors can ultimately generate a large intracellular response due to activation of kinase cascades. This is referred to as:

binary fission

In bacterial cell division, the cell divides into two nearly equal halves.  This process is called:

homologous chromosomes

The two copies of each type of chromosome found in normal somatic (body) cells in an organism, throughout the cell cycle are called:

16

If there are 32 sister chromatids in a normal somatic cell, how many chromosomes are there? 

G1 to S to G2 to mitosis to cytokinesis

What is the sequence of events in a typical eukaryotic cell cycle?

interphase

What is the portion of the cell cycle during which the chromosomes are invisible under the light microscope because they are not yet condensed?

If they cannot, it suggests that they aren't properly attached to the spindle microtubules, and thus won't separate properly during anaphase.

Why is it so important that all of the chromosomes align on the metaphase plate during metaphase?

Cyclins

The progress of the eukaryotic cell cycle is regulated primarily by what proteins?

Meiosis 

______ is a process of nuclear division which reduces the number of chromosomes per cell from 2 sets to 1 set.  

meiosis 

In life cycles that alternate between haploid and diploid stages, fertilization doubles the number of chromosomes per cell while ______ reduces it in half.  

crossing over 

Homologous chromosomes pair along their length during prophase I of meiosis. While two homologues are paired, genetic exchange may occur between them in a process called ________.  

two 

Diploid organisms use meiosis to produce haploid cells. Meiosis consists of how many rounds of nuclear division?  

zygote. 

The cell produced by the fusion of an egg and a sperm is the  

germ-line cells. 

In animals, the cells that will eventually undergo meiosis to produce gametes are set aside early in development. These are called  

prophase I. 

Crossing over between homologous chromosomes takes place during  

The way one pair of homologues lines up along the metaphase plate does not affect how any other pair lines up. 

Which best describes the process of independent assortment? 

mitosis

All of the following increase genetic variation EXCEPT  

failure of 1 homologous pair to segregate during meiosis.

In 95% of cases of Down's syndrome, there is one extra chromosome (number 21) in every cell. This aneuploid condition is most likely the result of 

genes

In modern terminology, Mendel’s heredity “factors” are called  

phenotype

The observable expression of the genes present in an organism is called its  

alleles

Alternate forms of the same gene are called  

3 yellow: 1 green

In Mendel's experiments on seed color in pea plants, when a dominant yellow seed-bearing plant was crossed with a recessive green seed-bearing plant, what was the approximate phenotypic ratio among the F2 generation? 

heterozygous

If fertilization involves two gametes that contain different alleles of a given gene, the resulting offspring is  

test cross 

What type of cross is used to determine if an individual with the dominant form of a trait is homozygous or heterozygous?  

purple flowers, tall 

Let P = purple flowers and p = white, and T = tall plants and t = dwarf. If the upper case letters represent the dominant alleles, what is the phenotype of a plant with the genotype PpTt?  

non-homologous chromosomes segregate independently of each other. 

Mendel's Principle of Independent Assortment states that different pairs of  

autosomes

Of the 23 pairs of human chromosomes, 22 pairs are homologous and are found in both males and females. These are called ________.  

21

In humans, individuals with trisomy of chromosome ______ most likely to survive until adulthood.  

for diagnosis of genetic disorders. 

Amniocentesis is a procedure that is normally used  

be female because each cell lacks a Y chromosome. 

In humans, if non-disjunction led to an individual with a genotype of XO, that person would  

In humans, the male determines the gender of the offspring, and in birds the female determines the gender. 

Male humans have an X and Y sex chromosome, while females have two X chromosomes. In birds, the female has a Z and a W sex chromosome, while the male has two Z chromosomes. Which of the following statements is accurate about which parent determines the gender of the offspring?  

1

How many Barr bodies does a normal human female contain in each diploid cell?  

double helix

Watson & Crick developed a model of DNA in which the two strands twist into the shape of a ____. 

complementary 

Because the two strands of a DNA molecule are ________ to each other, either one can be used as a template to reconstruct the other.  

semiconservative method. 

The method of DNA replication, where each original strand is used as a template to build a new strand, is called the 

polymerase 

Which enzyme adds new nucleotides to the end of a growing strand?  

A = T and G = C

Chargaff's rules for the pairing of nitrogen bases is  

discontinuous. 

The lagging strand is replicated with a series of Okazaki fragments and that is why its synthesis is considered to be 

The newly synthesized DNA is packaged into one nucleus, and the original DNA is packaged into another nucleus. 

Which of the following statements about DNA replication is false?  

36% 

If 14% of the nucleotides from a DNA molecule contain the base T, what percent will contain the base G?  

DNA helicase 

During replication, which enzyme unwinds the DNA double helix?  

using multiple origins of replication on each chromosome. 

Eukaryotic organisms speed up the process of DNA replication by  

Franklin

Who provided X-ray diffraction photographs of purified DNA fibers that suggested a helical structure with a consistent diameter of about 2 nm and a complete helical turn every 3.4 nm?  

purines and pyrimidines 

If we think of the DNA double helix as a twisted ladder, what makes up the rungs or steps of the ladder?  

proteins 

DNA affects the traits of an organism by providing the instructions for synthesizing _______.  

transcription 

Gene expression involves two phases, ___________ and translation.  

promoter 

To begin transcription, RNA polymerase must bind to a segment of DNA called the ____.  

non-coding 

The strand of DNA that is not transcribed is called the ______ strand.  

codons

1. Crick and his colleagues proposed that the genetic code consists of a series of blocks of information, called ______, each corresponding to one amino acid in an encoded protein.  

splicing

1. During transcription of mRNA in eukaryotes, some sequences are cut out of the primary transcript and the remaining sequences are joined together. This processing of mRNA is called _________.  

ribosomes

1. The polypeptide-making organelles, which consist of protein combined with RNA, are called  

Inside the nucleus. 

In eukaryotic cells, transcription occurs  

64

1. How many unique mRNA codons can be constructed from the four different RNA nucleotides?  

release factors. 

Codons that serve as "stop" signals for translation are recognized by  

peptide

When a polypeptide is being assembled, the bond that forms between a newly added amino acid and the previous amino acid in the chain is a _________ bond.  

removal of exons from the pre-mRNA. 

In eukaryotes, pre-mRNA processing may involve all of the following except  

DNA→ RNA→ proteins. 

Which of the following is a correct flow of gene expression?

mRNA

In eukaryotes, the 3' poly-A tail is attached to  

homeostasis

The maintenance of a constant environment in a cell is called __________. 

stable

Eukaryotic cell mRNA transcripts can remain in the cell for hours because they are  

specific transcription factors.

Enhancers are the binding sites for the 

structural motifs. 

The DNA-binding proteins of almost all regulatory proteins use one of a small set of shapes that enable them to fit into the DNA major groove. These shapes are called  

is only rarely available; producing enzymes all the time is costly.

The lac operon regulatory system is important to bacteria primarily because lactose 

repressor

A protein that regulates transcription by binding to the operator is known as the