Chapter 11

Question 1

Gene Expression means that ___

Answer 1

not all genes are turned on all the time

Question 2

Gene regulation is the ability of a gene to ______________________

Answer 2

turn on/off a specific phenotype

Question 3

what is differentation in gene expression

Answer 3

allows the embryonic stem cells to become different specialized cells

Question 4

How would gene expression change as an individual ages from infacy into adulthood

Answer 4

it changes to send energy where is needed
EX: Hair color changes to grey to remove energy from that cell

Question 5

Gene expression: DNA -> _____ -> _____ -> Proteins

Answer 5

DNA -> mRNA -> amino acids -> Proteins

Question 6

identify the benefit of E coli only making enzymes to use lactose when lactose is present and glucose is absent

Answer 6

it allows it to only use that energy when both factors are present, creating efficent energy use

Question 7

Humans begin as ______ and ______ which form a _______

Answer 7

egg/sperm which form a zygote

Question 8

What types of genes must be expressed in the phenotype of nervous system cells

Answer 8

Neurotransmitter-related genes

Question 9

What types of genes must be expressed in the phenotype of Skin cells

Answer 9

sensory receptor genes

Question 10

What types of genes must be expressed in the phenotype of White Blood Cells

Answer 10

antigen receptor genes

Question 11

What types of genes must be expressed in the phenotype of Muscles

Answer 11

contractile protein genes

Question 12

What types of genes must be expressed in the phenotype of Red blood cells

Answer 12

hemoglobin genes

Question 13

the tighter packed the genes are the ______ expression is

Answer 13

harder

Question 14

Define metylation in Gene expression

Answer 14

occurs when a methyl group, -CH3, attachs to the cytosine on DNA, keeping the gene condensed and not expressed

Question 15

Can methylated DNA be passed down? What is this called?

Answer 15

Yes
Epigenetic inheritance

Question 16

Define Epigenetic inheritance

Answer 16

not invloving nucleotide sequence
passed through Daugther cells what genes are methylated or not

Question 17

In Women: ______ in Embryotic development one of the two X chromosomes in each cell becomes inactive by condensing tightly into a _______

Answer 17

Early
Barr Body

Question 18

Why is X inactivation important

Answer 18

to balance representation of genes

Question 19

How does X inactivation contribute to coat color in animals like tortoiseshell cats

Answer 19

Which X is inactivated is random so it creates patches with different inactivations

Question 20

what are homeotic genes

Answer 20

genes that are “Master control genees” control many other genes and help determine which end of a zygote is head of tail and the position of major body parts

Question 21

What happens if homeotic genes are mutated

Answer 21

mmutted anatomy that can result in death

Question 22

Reproductive cloning is achieved through ___________

Answer 22

nuclear transplantation

Question 23

Steps of reproductive cloning

Answer 23

1.) nucleus of an egg is replaced with nucleus of adult somatic ell
2.) the nucleus divides
3.) BLASTOCYST is formed: hollow ball of ~100 cells
4.) Bastocyst is implanted

Question 24

List some animals that have been cloned

Answer 24

sheep, dog, cat, pig, fly, human

Question 25

Clones will be identical to ____________

Answer 25

somatic cell donor

Question 26

What is therapeutic cloning

Answer 26

creates organs

Question 27

How are adult stem cells used in therapeutic cloning?

Answer 27

can be used for SOME specialized cells

Question 28

what does the term pluripotent mean? What type of stem cells are usually pluripotent

Answer 28

Embryotic all specialized cells are avalible

Question 29

Oncogenes Proto-oncogenes Tumor suppressor: Tumor:

Answer 29

O: Cancer causing cells PO: Normal cell w/ potental to be cancerous TS: Inhibits uncontrolled cell division (P53 gene) T: Uncontrolled growth

Question 30

How can a proto-oncogene become a oncogene

Answer 30

Chemical: Drugs/alcohol Physical: X-ray/UV Virus/Bacteria

Question 31

What are the top 5 carcinogenes

Answer 31

Tobacco, smoking, processed meat, pollution, and UV rays

Question 32

Decribe how carcinogens cause cancer

Answer 32

Continuing exposure to these things causes mutations to happen in your genes, and if you have 4 or more mutations you are going to likely get cancer.

Question 33

How could lifestyle increase/decrease cancer risk

Answer 33

Smoking greatly increases, age also increases Healthy diet can decrease

Question 34

Since all of the cells of the body (execpt gametes) have the same genotype, explain how different cell types can express different phenotypes

Answer 34

Because environmental factors and how someone grows up will alter their phenotypes.

Question 35

List some benefits of the ability to turn certain genes on and off

Answer 35

Allows response to environmental changes

Question 36

What is a fertilized egg called? How many chromosomes does a human on have?

Answer 36

Zygote; 46

Question 37

Explain the concept of differentiation in eukaryotes

Answer 37

Cells become specialized in structure and function

Question 38

How do all of the trillions of cells in the human body express the correct genes for their function?

Answer 38

Specialized gene expression

Question 39

Desribe how DNA is packaged into Chromosomes. How does the packaging of DNA affect gene expression?

Answer 39

Histones: PRotein for DNA packagin Nucleosome: 8 histones + DNA Linker: Streches of DNA that connect to a nucleosome

Question 40

if a gene is tightly packed will it express more or less easily?

Answer 40

less

Question 41

Describe DNA methylation and what hapens to a gene that is methylated

Answer 41

Add methyl group to cytocine to turn gene off It no longer expresses that gene

Question 42

Define Epigenetic inheritance

Answer 42

inheritance of traits transmitted by mechanisms not directly invloving nucleotide senquence

Question 43

Why don't Females have double the amount of proteins coded for by the X Chromosome?

Answer 43

X Inactivation: one X Chromosome in each somatic cell inactivates in females by condensing into barr body effect

Question 44

how are barr bodies formed

Answer 44

one X chromosome becomes inactive and condenses tightly

Question 45

Are most eukaryotic genes turned on or off? Which is more imprtant in gene expression, activators or repressors?

Answer 45

Most genes are turned off. They are both important, because repressors decrease/halt transcription and turn off certain genes in the body, and activators regulate your gene expression by promoting transcription.

Question 46

What is a homeotic gene and why are they important

Answer 46

Master control genes that determine the anatomy of the body Important for normal body arrangement

Question 47

Explain the steps in Eukaryotic cloning

Answer 47

Replace nucleus of an egg cell (receptient) with nucelus of an adult somatic cell (Donor)

Question 48

Explain why embryotic stem cells are harvested at a particular time in development

Answer 48

Embryotic stem cells give rise to all specialized cells while adult ones only have some

Question 49

How does reproductive cloning differ from therapeutic cloning?

Answer 49

Theraputic is for repair of damaged/diseased organs Reproductive makes a whole new organism

Question 50

What is an adult stem cell? what are they used for and what are their limitations?

Answer 50

Stem cells from adults only have some specialized cells, used for theraputic cloning

Question 51

Define oncogenes, proto=oncogenes, and tumor-suppressor genes and their importance

Answer 51

Onco: Cancer causing genes Proto: normal genes w/ potential to become an oncogene Tumor Suppressor: Inhibit uncontrolled cell division Important in the identification and suppression of cancer

Question 52

What might make a proto-oncogene become an oncogene?

Answer 52

demethylation

Question 53

How do oncogenes cause cancer? how do tumor supproessor genes counteract oncogenes?

Answer 53

Oncogenes cause cancer because they cause the cell to divide and multiply uncontrollably. Tumor suppresor genes code for proteins that prevent or suppress cancer in an active form. They also code for apoptosis, or cell self deleting.

Question 54

what is meant by: "Most cancers are caused by more than one mutation"? How does this work? What errors must occur to allow the formation of a tumor

Answer 54

Mitosis error Gradual accumulation of mutations that cenverts into proto-oncogenes to oncogenes and mutations/loss of tumor-suppressor genes

Question 55

Describe a carcinogen. Identify the most common carcinogen

Answer 55

Cancer causing agents. Drugs (Tobacco)

Question 56

How do life choices counteract carcinogens?

Answer 56

Whatch what you eat and put in your body

Question 57

Would 2 clones animals look and behave identically? Explain how identical twins might express different proteins

Answer 57

They would look the same but act differently as they have different brains Epigenetic inheritance

Question 58

_______ gene help determines where legs and arms will develop.

Answer 58

Homeotic gene

Question 59

The units of hereditary information are called

Answer 59

Genes

Question 60

During RNA splicing, _____ are removed from the original mRNA sequence to produce the resulting mRNA.

Answer 60

introns

Question 61

A repressor is controlled by a ________.

Answer 61

regulatory gene

Question 62

Due to alternative ________ one gene can result in multiple polypeptides.

Answer 62

RNA splicing

Question 63

Embryonic stem cells are harvested from the _________.

Answer 63

blastocyst

Question 64

Prokaryotic ____________ initiates gene transcription without the assistance of transcription factors.

Answer 64

RNA polymerase

Question 65

T/F The tortoiseshell trait in cats is found on the X chromosome. Due to X chromosome inactivation, tortoiseshell cats are always females.

Answer 65

FALSE

Question 66

A gene that when present can cause cancer is called an _______-.

Answer 66

oncogene