Extra Notes

Question 1

The carbohydrates and peptides cross bridges the bacterial cell have ____ ___ have provide ___ __

Answer 1

D-amino acids, structural integrity

Question 2

A polymerase found in thermophile archaeans that is used in PCR because of its stability and accuracy in high temperatures

Answer 2

Pfu polymerase

Question 3

Some archaea contain ___ in their cell walls

Answer 3

pseudomurein

Question 4

___ is the initiator amino acid for protein synthesis for archaea and eukarya. In contrast, bacteria use _____

Answer 4

methionine, formyl-methionine

Question 5

catalyze the tRNA chargin reaction and join a specific amino acid to the associated tRNA molecule

Answer 5

Aminoacyl-tRNA synthetases

Question 6

Explains that the exact base pair of the third nucleotide in the codon is often not required or is considered more of a “relaxed” position

Answer 6

Wobble theory

Question 7

signal peptides are a sequence of approximately ____ amino acids functioning in ____ ___ to target the ____ ___. They are also utilized by bacteria in order to target the cell’s ___ ___.

Answer 7

20, signalling proteins, rough ER, plasma membrane

Question 8

Signal recognition particles (SRP) are a type of ___ __. This functions in identifying the signal peptide as it is released by the ___ and then directs the ribosome to the __ where it comes in contact with certain ___ __.

Answer 8

protein-RNA complex, ribosome, ER, receptor proteins

Question 9

The synthesis of polypeptides begins within the __ with the use of ____ ribosomes. If there is a signal peptide present, the ____ binds to the available signal peptide, which momentarily stops polypeptide synthesis. The SRP escorts the ribosomes to a __ ____ within a protein complex located in the ___ ____ called which ____ ____, which then forms a ___ within it.

Answer 9

cytosol, free, SRP, protein receptor, ER membrane, translocation complex, pore

Question 10

Once the ribosome is attached to the ER, the SRP is ___ which allows for polypeptide synthesis to ___ while simultaneously allowing for the growing peptide to translocate into the ___ __ via the pore. An enzyme within the translocation complex then cleaves the __ __ removing it. The completed polypeptide exits the ribosome by being released into the ER lumen to be secreted from the cell via the ___ ___, or remaining attached as part of the __ _____.

Answer 10

released, continue, ER lumen, signal peptide, golgi apparatus, endomembrane system

Question 11

If the peptide continues translating until completion, it becomes a __ ribosome, which synthesizes proteins that remain functioning in the ___.

Answer 11

free, cytosol

Question 12

If the peptide receives a signal and attaches to the ER, it becomes a ____ ribosome that function in synthesizing proteins that become part of the ____ system and proteins that are released from ___ ____

Answer 12

bound, endomembrane, individual cells

Question 13

Signal peptides may also signal polypeptides to target locations other than the ___. These include ___, __ and the ____ of the nucleus. However translation is ___ first in the cytosol

Answer 13

ER, mitochondria, chloroplasts, lumen, completed

Question 14

Both bound and free ribosomes are ___. As a result, they have the ability to ___ between being used as one or the other

Answer 14

identical, alternate

Question 15

Although transcription and translation can occur simultaneously in ____ both prokaryotes and eukaryotes have the ability to utilize multiple ___ in order to translate many of 1 mRNA molecule at the same time.

Answer 15

prokaryotes, ribosomes

Question 16

The helix turn helix is composed of two ___ __ connected by a short non-helical chain of __ ___ (turn). One of the helices is the __ ___ which binds to the major groove of the DNA, while the other helix plays a role in ___ this interaction. Most sequences recognized by these motifs occur in ___. Due to greater number of ____ __ there is a much higher affinity between the protein and the DNA

Answer 16

alpha helices, amino acids, recognition helix, stabilizing, pairs, DNA-binding sites

Question 17

A homeodomain motif is a subset of helix-turn-helix motifs related to the ____. It also contains a __ __ which binds to the major groove of DNA

Answer 17

homeobox, recognition helix

Question 18

The zinc finger motif uses ___ atoms to aid in __ ___. It connects an __ __ to a __ ___ segment in a way that allows the alpha helix to bind to the major groove of the DNA molecule. It is common for this to happen with more than one zinc atom and this results in ____ of the bond between the protein and DNA

Answer 18

zinc, alpha helix, beta sheet, stabilization

Question 19

The leucine zipper motif allows several ___ of a given protein to bind to a DNA molecule. These protein subunits contain ___ __ and interact with other subunits on the same protein to create a ___ shape. The major grooves of DNA are then able to interact with the arms of this shape.

Answer 19

subunits, hydrophobic leucine, Y

Question 20

Small RNAs involves both _____ and _____ ___ ____ used to silence gene expression

Answer 20

micro-RNA, small interfering RNA

Question 21

In eukarya, histone ____ to the histone tail promotes transcription by ___ the chromatin structure, while ____ results in ___ transcription

Answer 21

acetylation, decondensing, methylation, reduced

Question 22

Long stretches of ____ DNA are more heavily _____ compared to. active DNA regions. Methylation patterns can be ___ once enzymes methylate the needed daughter strands

Answer 22

inactive, methylated, inherited

Question 23

General transcription factors are crucial for every ____ __. Some can bind directly to the DNA sequences, but others bind to ___

Answer 23

protein-coding genes, proteins

Question 24

Specific transcription factors are either ____ that bind directly to a control element DNA or to an ____. ___ have two domains known as the ____ domain and ___ domains

Answer 24

repressors, activator, activators, DNA-binding, activation

Question 25

noncoding DNA that functions as binding sites for transcriptional factors

Answer 25

control elements

Question 26

Control elements closer to the promoter

Answer 26

proximal control elements

Question 27

____ are usually made up of ten control elements farther from the promoter region of a specific gene. For activators to bind to an enhancer proteins __ the DNA to bring the activators closer to __ ___ that trigger the interaction with the promoter’s general transcription factors

Answer 27

enhancer, bend, mediator proteins

Question 28

___ ___ are maternal substances in the ____ of the unfertilized egg that alter the early development of the zygote. As the zygotic cell develops the ___ of the daughter cells are exposed to different amounts of ____ __ which determines their developmental fate and alters which ___ they express

Answer 28

cytoplasmic determinants, cytoplasm, nuclei, maternal substances, genes

Question 29

molecular directions used to control pattern formation

Answer 29

positional information

Question 30

when a mutation phenotype in the mother causes a mutant phenotype in the offspring regardless of the offspring’s genotype; seen in mitochondrial diseases

Answer 30

maternal effect gene

Question 31

gradient of substances that orient the axes and features of embryos

Answer 31

morphogens

Question 32

Genes involved in regular gene expression are ______. The ____ genes are responsible for coding for a G protein that drives the ___ and ___ of cells.

Answer 32

proto-oncogenes, ras, growth, development

Question 33

mutated proto-oncogene that results in higher risk of cancer; when the upregulation of a gene causes cancer

Answer 33

oncogenes

Question 34

In prokaryotes, the ___ is the on off switch in a gene near the promoter. It functions by inhibit ___ __ access to the gene. The _____ is made up of the operator, a controlled DNA ____, and a ___. It functions in unity to produce an mRNA strand. A ____ operon can be turned off while an ____ operon is an inactive operon that can be turned on

Answer 34

operator, RNA polymerase, operon, stretch, promoter, repressible, inducible

Question 35

A _____ binds to a specific operator, represses RNA polymerase binding and transcription of genes in prokaryotes. The __ __ encodes the gene for a repressor protein and is usually continually active at a __ ____. The ___ is a small molecules that aids repressor proteins to switch and operon off. The ____ is a small molecule that can inactivate a repressor, increasing expression of a gene

Answer 35

repressor, regulatory gene, low rate, corepressor, inducer

Question 36

Prokaryotes also use ___ factors to regulate operon activity. ____ is a small molecule that binds to a _____ ___ ____ (CRP) to promote gene transcription. Too much of a gene product ____ cAMP

Answer 36

environmental, cAMP, camp receptor protein, decreases

Question 37

In the lac operon, when lactose is absent, the ___ __ binds to the operator, preventing transcription. When lactose or ____ is present, it binds to the repressor and makes it let go of the operator, increasing transcription. _____ binds to and activates the ___, increasing transcription.

Answer 37

lac repressor, allolactose, cAMP, CRP

Question 38

____ is study of heritable changes in the expression of genes due to modifications that do not alter the ___ __ but instead modify how and if the sequence is ____.

Answer 38

epigenetics, nucleotide sequence, read

Question 39

DNA methylation adds methyl groups to the ___ ___ on a DNA strand and results in ___ gene expression. The methyl group can ___ block transcription ___ from binding, and it can also recruit other proteins that cause it to wrap more tightly around ____.

Answer 39

nitrogenous bases, decrease, physically, histones

Question 40

Histone acetylation is the addition of an ____ group to an amino acid _____ found in the histone ___ that protrude from the histone core. Adding an acetyl group to histones weakens the __ ___ between DNA and histone proteins. This causes the DNA to loosen its wrapping around the histones and make DNA more ___, leading to ____ gene expression.

Answer 40

CH3O, lysene, tail, electrostatic interactions, accessible, increased

Question 41

in mammalian females, two copies of the X chromosome are present but the body does not want to ____ the genes on these chromosomes. Therefore, only one X chromosome is __ __ to maintain correct levels of gene expression. The other X chromosome is ____ and has a high amount of DNA ___. The inactive X chromosome forms a compact structure called a __ ___ which remains on the ____ of the cell nucleus. This is ___ through many mitotic divisions in female mammalian cells.

Answer 41

over-express, fully active, silenced, methylation, barr body, periphery, inherited

Question 42

In the ovaries, the silenced X chromosome is ___ to ensure that each gamete produced has an active X chromosome during ___.

Answer 42

reactivated, meiosis

Question 43

__ ___ is a condition where offspring only inherit only one X chromosome. This is a problem because not ___ genes are usually silenced in X chromosome inactivation

Answer 43

turner syndrome, all

Question 44

____ ___ is the differential expression of a gene depending on which parent the gene was inherited from. It involves either ___ of one allele in a gamete or ___ of the other allele. These are also ____ throughout many mitotic divisions as the organism develops. If this process fails to occur there would be ___ gene product from both alleles remaining active.

Answer 44

genomic imprinting, silencing, activation, inherited, excess

Question 45

In Prader-Willi syndrome, the ____ copy of chromosome ___ is deleted or mutated. Because the __ copies of the genes are already inactive, there is an ___ of necessary gene products and the child develops a number of disorders.

Answer 45

paternal, 15, maternal, absence

Question 46

In angelman syndrome, the copies of the ___ genes on chromosome ____ deleted or mutated, while the -___ chromosome is imprinted.

Answer 46

maternal, 15, paternal

Question 47

The mutant form of the agouti gene results in ___ hair instead of black and predisposes the mice towards becoming ____.

Answer 47

yellow, obese

Question 48

In the agouti experimentally ___ __ mice were split into two groups. One was fed a normal diet, while the other was fed with food supplemented with additional ___ groups. The normal diet group became ___ and ____ due to their fully expressed mutated agouti gene. The group fed a supplemental diet had a normal __ colour and were non-obese.

Answer 48

genetically identical, methyl, yellow, obese, brown

Question 49

In some reptiles, gender is determined by environmental _____ during the ___ development called the _____ _____. In pattern I development, males result from ___ temperatures and females result from ___ temperatures. For example, ___. In pattern II development, female offspring develop in ___ and ___ temperatures, while males develop in ___ temperatures. For example, ____.

Answer 49

temperature, embryonic, thermosensitive period, low, high, turtles, low, high, intermediate, crocodiles

Question 50

The biological mechanisms for temperature dependent __ ___ are believed to be ___ in nature, involving acetylation, methylation and ___ ___ to modify ___ pathways leading to differential __ ___ development

Answer 50

sex determination, epigenetic, non-coding RNA, hormonal, sex organ

Question 51

In honeybees, when a female larvae is fed __ ___ through development, DNA methylation is ___ and gene expression allows for development of the ___ phenotype. This queen is ___ lives ____, develops more quickly and has functional ____. If a female larvae is instead fed a normal diet of __. and ___, DNA methylation occurs and the genes that lead to development towards the queen morphology are ___ resulting in a ___ phenotype instead

Answer 51

royal jelly, blocked, queen, bigger, longer, ovaries, pollen, nector, silenced, worker

Question 52

Cloning has low levels of ___ and high ___ levels because the nuclei being taken from ____ organisms are in fully ___ cells so the DNA of the clones were starting embryogenesis with ____ of genes that that may be necessary for normal development

Answer 52

efficiency, defect, adult, differentiated, suppression