Veterinary Genetics Flashcards
All information that was taught to me while attending Vanier College's "Animal Health Technology" Program, located in St-Laurent Montreal.
1
Q
What is genetics
A
The study of transmission or inheritance of characteristics from one generation to the next
2
Q
What are the two types of heritable characteristics
A
Anatomical and functional
3
Q
List a few reasons why the pea plant was a good study model for early day genetics
A
It was easy to cultivate, several distinct varieties, short lifecycle, hermaphroditic part, self fertilizing
4
Q
What does true breeding mean
A
Offspring always resemble parents in the particular trait
5
Q
What is a mono hybrid cross
A
A cross between individuals that differ only in a single characteristic
6
Q
Explain Mendels law of segregation
A
Paired units separate during gamete formation
7
Q
What is a gene
A
A unit of information about a specific trait passed from parents to offspring
8
Q
What is a locus
A
Specific location where a gene sits on a chromosome
9
Q
What is a genome
A
The complete set of genes that determine all the characteristics of an individual
10
Q
What are alleles
A
Different versions of the same trait
11
Q
What does homologous mean
A
Similar
12
Q
What does heterozygous mean
A
Nonidentical alleles
13
Q
What is a genotype
A
The particular alleles an individual carries for a given characteristic example RR
14
Q
What is phenotype
A
observable traits of an individual
15
Q
What are the four type of nucleotide bases
A
A (adenine), C (cytosine), G (guanine), T (thymine)
16
Q
How do the bases pair
A
A with T, C with G
17
Q
Describe how DNA information gets translated into protein
A
DNA, transcription, RNA, translation, protein
18
Q
In RNA what is different about the bases
A
There is no T it is now U, uracil
19
Q
What are the three types of gene mutations
A
Substitution, insertion, deletion
20
Q
Where does mitosis occur
A
Somatic and germ cells
21
Q
Where does meiosis occurred
A
Only in germ cells
22
Q
When are chromosomes the most tightly condensed in mitosis
A
Metaphase
23
Q
What are dihybrid crosses
A
Crosses between individuals whose phenotypes differ for two characteristics
24
Q
What is the formula for finding the number of possible gametes
A
2N, where n is the number of heterozygous gene pairs
25
How do you determine the probability of two or more independent events occurring simultaneously
It is the product of their individual probabilities (multiply them)
26
What is special. About dichotomous diagrams
It cannot be used to study genes linked on the same chromosome
27
What are poly hybrid crosses
Crosses between individuals whose phenotypes differ for three or more traits
28
Describe the law of independent assortment
Each pair of homologous chromosomes are sorted into gametes independently of how other pairs of homologous chromosomes are sorted
29
Describe complete dominance
Occurs when the effect of one allele completely masks the effect of the other allele for a given trait. Cannot distinguish phenotype of heterozygous from homozygous dominant
30
Describe incomplete dominance
cross between two different homozygous individuals produces offspring whose phenotype is intermediate or a mix of that of the parents
31
Describe codominance
Occurs when non-identical alleles are both expressed visibly and independently to produce a new phenotype. Not a mix or intermediate form of both alleles. Example roan hair
32
What is pleiotropy
The ability of a given gene to influence expression of two or more traits
33
What does a Pleiotropic gene do
Influences the expression of traits that are clearly phenotypically different from each other
34
What happens if you have a W Gene
You're completely white. The gene is Pleiotropic. Can influence eyecolor
35
What happens if you're Mm
You're a blue Merle
36
What happens if you're mm
You're a tricolor
37
What can the Merle gene cause?
Coat color dilution as well as deafness,blindness and sterility
38
What happens if you're MM
All white, generally dead and blind and often sterile
39
What is penetrance
Proportion of individuals carrying a particular gene that also expresses the expected associated trait
40
What is complete penetrance
Hundred percent of individuals looking the exact same way (for a gene)
41
What is incomplete penetrance
A faction of individuals looking the same way (for a trait)
42
What is expressivity
When I given genotype is visibly expressed but the degree of expression of the expected phenotype can be variable in different individuals. Example: 2 patients suffering from the same disease but with different severity
43
What is epistasis
The act of stopping and masking
44
What is a gene that masks called
Epistatic gene
45
What is a gene that are masked called
Hypostatic gene
46
What happens when epistasis occurs
No longer have the expected phenotypic ratio for dihybrid crosses
47
What is dominate epistasis
Strong epistasis. only one copy is needed. Manifests itself in heterozygous and homozygous dominant
48
What is recessive epistasis
Both copies of the epistatic gene are required. Manifest itself exclusively in homozygous recessive
49
What happens if you are WW or Ww
You will be white
50
If you are wwB what are you
Black
51
If you are wwbb what are you
Brown
52
If you are WwBb what are you
White
53
What two genes are examples of recessive epistasis
Agouti gene, color gene
54
If you are aa what are you
Solid color
55
What happens if you are cc
Albino
56
What is collaboration
Interaction between two different genes that influence the same trait to produce a new phenotype that neither gene could produce alone. Example comb shape in chickens
57
What are modifier genes
Genes that influence the expression of other genes through their expressed product
58
In the absence of the main gene what do modifier genes do
They have no visible effect
59
What are examples of some things that modifier genes have changed
Quantity of black spots in Holstein cattle, tail length in Manx cats
60
Describe genetic recombination
Establishment of new allele combinations and offspring. Great variations in details of their traits
61
What are the three ways to establish new allele combinations
1. Crossing over between homologous chromosomes2. Independent around the assortment of homologous chromosomes into gametes3. Random fusion of gametes during fertilization
62
When does crossing over occur
In prophase one of meiosis
63
When does independent assortment occur
Metaphase one of meiosis
64
What is the specific area where chromatids cross each other and exchange genetic material called
Chiasma
65
How do you know if gametes are recombinant or non-recombinant
Recombinant genes carry a new combination of alleles. Non-recombinant genes contain the same genotype as the parent chromosome
66
The greater the distance between the two genes the ______ the chance that crossover will occur
Greater
67
Is frequency and crossover between two location proportional to distance or nonproportional to distance
Proportional
68
What is a genetic map
A graphical representation of the order in which linked genes are distributed along a chromosome. Also indicates the distance that separates a given gene from other genes
69
How do you calculate percent recombination
Number of recombinants divided by total number of individuals times 100
70
What does each percent mean in terms of units of distance
1% = 1 unit of distance
71
What is the unit used with genetic maps
Centimorgans cM
72
What is the maximum recombination value
50%
73
What is cytogenetics
A bunch of genetics devoted to the study of number, structure, behavior of chromosomes both in normal, and pathological state in the cell
74
What is a karyotype.
It photographic or schematic representation of a set of chromosomes in metaphase from somatic cell of a given species
75
What does karyotyping show
Number of chromosomes, structure which is species specific. Allows you to sex chromosomes and chromosomal abnormalities
76
What are the two types of chromosomal abnormalities
Changes in chromosome number, changes in chromosome structure
77
Which of the two chromosomal abnormalities are the cause of most embryonic deaths
Changes in chromosome number. More than 50% of human miscarriages
78
What is euploidy variation
When an entire set of chromosomes is abnormal in number
79
What is it aneuploidy variation
Where one or a few individual chromosomes or are abnormal in number
80
How many chromosomes does a haploid individual have
23
81
How many pairs of chromosomes does a diploid individual
46
82
How many pairs of chromosomes does a triploid individual have
69
83
How many pairs of chromosomes does a tetraploid individual have
92
84
What is abnormal haploidy
Development of non-fertilized ovum into an embryo. Undergoes mitosis. Most often in chickens and they generally die
85
What is polyploidy
More than one pair of homologous chromosomes. Triploidy is most common
86
What is polyploidy due too
Due to Polyspermy. Fertilization by more than one sperm
87
What is digyny
Two female pro nuclei with one male pronucleus
88
How does tetraploidy occur
The cell goes through DNA duplication and mitosis but does not undergo nuclear division
89
What is Nullisomy
Minus one pair of chromosomes 2n-2
90
What is monosomy
Minus One chromosome in the pair. 2n-1 Turner syndrome
91
What is polysomy
Increased numbers of chromosomes
92
What are the two types of Polysomy
Trisomy and tetrasomy
93
What is trisomy
Only increased by one extra chromosome. Down syndrome
94
What is Tetrasomy
Increased by 2 chromosomes
95
What are aneuploidy variations due to
Non-dis junction. Failure to separate
96
What are interspecies matings
Meetings between two different species. Donkey plus horse equals mule
97
When is it easier to obtain a hybrid in interspecies mating
When the mail contributes a lower amount of chromosomes
98
what is specific about AutoSomal chromosomes
Each pair is similar in length shape and gene sequence
99
If you have a homologous pair of sex chromosomes what type of sex are you
Homogametic sex (xx, zz)
100
If you have a non homologous pair of sex chromosomes what type of Sex are you
Heterogametic sex (xy, zw)
101
How do scientists do sperm sorting
They put a fluorescent marker that binds to DNA. The fluorescent glow is stronger on the x then y.
102
What is a pseudo-autosomal region
Only homologous area where crossover may occur during prophase one
103
What is SRy
Sex determining region y. Males only
104
What does the presence of a Barr body indicate
An inactivated x
105
Before sexual differentiation what do both males and females possess
Gonads and Wolffian and Müllerian ducts
106
What is sexual differentiation
When the embryo of undifferentiated sex turns into male or female
107
What does the SRy gene do
Is the master gene for sexual differentiation. Codes for protein that induces plus regulates reaction necessary for male sexual differentiation
108
With SRy what are the steps of sexual differentiation
Expression of SRy gene. differentiation of gonads into testicles. Male reproductive organs
109
Without the SRy gene what are the steps
Gonads to ovaries to female reproductive organs
110
What do testicles produce
Hormones for development of male reproductive system. Testosterone plus anti Müllerian hormone
111
What does testosterone do
Differentiation of wolffian duct. Seminal vesicles, ductus deferens plus epididymis. Develops penis and scrotum
112
What does the anti-Müllerian ducts do
Destroys Müllerian ducts plus prevents formation of female organs
113
What do ovaries produce
Estrogen
114
What is the difference between sex linked And autosomal traits
Autosomal traits are present in two copiesSRY present in one copy
115
Describe Autosomal mutation
If one allele is affected there's still another good copy
116
Describe sexual mutation
Sexual differentiation and health effects are caused
117
What are abnormal number of sex chromosomes due too
Non-disjunction of sex chromosomes
118
When nondisjunction of sex chromosomes happens in females: what's the outcome
XX or 0
119
When nondisjunction of sex chromosomes happens in males: what's the outcome
XY, XX, YY or O
120
With abnormal numbers of sex chromosomes what is affected
Phenotypes are usually not affected but sexual traits are usually affected
121
What is XO
Turner syndrome (dwarfism and no sexual development)
122
What is XXX
Trisomic female (tall + small head + delayed speech)
123
What is XXXX
Tetrasomic. More severe version of Trisomic symptoms
124
What is YO or YY
Never observed in live animals
125
What is XXY or XXXY
Klinefelter (male tortoiseshell cat➡️ sterile and no sexual behavior)
126
What is XYY
Criminal gene: stature increased + learning disability
127
What does intersexuality mean
Having both male and female characteristics. Hermaphrodite
128
What is gonadal intersexuality.
When you are wrong on the inside
129
What are the two types of gonadal intersexuality
XX: external female + testisXY: external male + ovaries
130
What are the two examples of phenotypic intersexuality
XX: ovaries plus external male genitals. XY: testes plus external female genitals
131
What is the only TrueType of hermaphrodite
Ovotestis. Both ovary + testical tissue
132
What is testicular feminization
Affects XY. Who's somatic cells do not respond to testosterone. Testees secrete testosterone but target tissues that don't respond. Unable to convert testosterone to active form
133
What is a freemartin
Sterile female born as a twin to a normal male
134
What is a Chimara
Two or more different populations of genetically distinct cells originating from different zygotes. To identify use karyotype of white blood cell
135
If it is a dominant X-linked mutation and the male is affected what will be the outcome for the offspring
All female offspring will be affected and no issue for males
136
If it is a dominant X-linked mutation in the female are affected what will happen to the offspring
Half will be affected half will be normal
137
If it is a recessive X-linked mutation in the male is affected what will happen to the offspring
None will be affected but all female will be carriers
138
If it is a recessive X-linked mutation and the female is a carrier what will happen to the Offspring
Half of the males will be affected half of the females will be carriers
139
Described as z linked traits
Allow for simple and rapid sexing at early age
140
What is a mosaic
Individual was cells having more than one genotype from a simple zygote
141
What is sexed influence genes
Genes whose phenotypic expression varies depending on the sex of the individual.
142
What are cats often selected because of
Coat type
143
What are hairs
Columns of bound dead cells organized in three layers Medulla cortex and cuticle
144
what are melanin pigments produced by
Melanocytes
145
Where in the hair is the melanin pigment deposited
In the Medela and cortex of primary hairs
146
How do melanocytes produce melanin
Melanocytes produce melanin from tyrosine in presence of tyrosinase
147
What is the hereditary inability to produce melanin called and what gene is responsible
Albinism and then gene is the recessive gene cc
148
What are the two types of melanin pigments responsible for all coat colors
Eumelanin and pheomelanin
149
What color do eumelanin granules make
Brown, black
150
What colors do pheomelanin granules make
Red, orange, yellow
151
Does pigment appear all at once or is a gradual
It is gradual. Pigments may be produced at various stages of development and some adult coloration is present in newborn, in others the coat color is modified until adult coat is completely developed
152
What is a wild type gene
The original gene
153
What are some environmental modifiers that can alter coat appearance
Age, disease, hair clipping, malnourishment, UV light, temperature, chemical agents
154
What is the wild type labeled with
+
155
What are all deviations from the wild type due to
Mutations
156
What is the original purebred cat
Tabby cat. The cat breeds that don't look like tabbies simply carry other types of genes that prevent the tabby coat pattern from appearing it is always present.
157
What is the eumelanin production gene
B+
158
What is the agouti gene
A+
159
What is the tabby Gene
T+
160
What does the B Gene do
Direct synthesis of black melanin by hair melanocytes, allows presence of black pigment and their variations. Anything not orange or cream
161
What is the agouti gene do
Controls pigment distribution within hair, distributes pigment unevenly within hair. alternating light and dark bands
162
What does the aa gene do
Solid coat
163
What does the A- gene do
Agouti
164
What does the tabby Gene do
Controls proportion and placement of agouti and uniform hairs on body. Determines coat pattern
165
What does a wild type cat genotype look like
A-B-T-C-
166
If a cat is aaBB he is what
Solid black
167
What are the basic coat colors
Black, chocolate, cinnamon, red
168
What are the dilutions of the basic coat colors
Blue, lilac, fawn, cream
169
What is b
Chocolate
170
What is b1
Cinnamon
171
What is the color difference due to
Different shape and different amounts of eumelanin pigment. Black pigments are sphyerical brown pigments are oval
172
What is the order of dominance for basic coat colors
B+(black)>b(chocolate)>b1(cinnamon)
173
What does the pheomelanin producing gene do
Red, orange, yellow colors. Wild type O+ allows expression of B allele. Mutant O of this gene is epistatic. Doesn't allow for expression of B allele
174
Where is the O or O+ gene located
Carried on chromosome x. Three phenotypes in females and only two in males
175
What does XO+ do
Wild type. No red pigment. Allows expression of B gene alleles (Blacks and browns)
176
What does XO do
Mutant. Epistatic over B gene. Red, orange, rusty.
177
What is XO also Epistatic over
aa. An orange cat will always have agouti hair it will never be solid orange
178
What is a Torti
Orange and black
179
What is a Torby
Orange black and white
180
What does the color dilution gene do
D+ allows for normal expression of B. dd dilutes the coAt to blue, lilac, fawn and cream
181
If individual is xOxO or xOy then
Red phenotype regardless of which alleles are present at B gene Loci. Impossible to determine which B alleles are present since masked
182
If a cat is S then
He is spotted white
183
If a cat is W gene he is
Completely white
184
If a cat has cc gene the he is
Albino
185
What is the wild type for white spotting
s+. No white spots produced
186
When S gene is present what happens
White spots are present in variable sizes
187
What is a bicolor cat
Half to two thirds white coat cat
188
What is a harlequin cat
Mostly white with color exclusively on head, tail, 2or 3 spots on back
189
What is A van cat
Only head and tail colored
190
What is the wild type for the w gene
w+. Allows expression of coat color genes
191
What is a pleiotropic gene
A gene that influences phenotypic expression of two or more traits
192
With the W gene what else can happen
Blue eyes and 60 to 70% of white cats, deafness in 40 to 50% of white cats. Extent to which iris color and hearing structures affected is variable
193
What is the order of dominance for the color extension gene
C+>cB ~ cS > c
194
What is a cB cat
Burmese. Slightly less intense paler color on body but not extremities.
195
What is a cS cat
Siamese. Significantly less intense body colored. Intensely colored points
196
What color are Siamese kittens born
White but extremities darkened overtime
197
What is that Chinchilla gene
This gene transforms agouti pattern into pattern where only tip of hair is colored. Must have agouti gene. ch+ wild type agouti striped hairs
198
If the cat is Ch whAt happens
Chinchilla tipped hair. only hair tip is coloured
199
What happens if the cat is i+
No inhibition of yellow colour
200
What happens if cat is I
Inhibition of color in normally yellow areas within hairs. They become silvery
201
If the cat is T- what is he
Wild type mackerel tabby
202
If a cat is tBtB what is he
Blotched, classic tabby
203
If the car is Ta- what is he
Abyssinian or ticked tabby
204
If a cat is L+ what is he
Short hair
205
If a cat is l what is he?
Long hair
206
If a cat is R what is he
Normal coat type
207
If a cat is r what is he
Cornish Rex
208
If a cat is re what is he
Devon Rex
209
If a cat is Hr what is he
Normal coat
210
If a cat is hr what is he
Sphinx
211
If a cat is wh what is he
Normal coat
212
If a cat is Wh what is he
American wirehaired
213
For dogs what were the most important traits that they were selected for
Shape and size
214
Many genes are involved in coat color and pattern in the domestic dog
10 genes involved
215
What does more variable mean
Greater Phenotypic variations
216
What is the eumelanin production gene controlled by
Controlled by Gene B. Mutant allele is b.
217
What is the color dilution gene control bye
D+ allows expression of pigment producing genes. Affects eumelanin little effect on pheomelanin
218
What color is black diluted too. What color is blue diluted too
Black is diluted to blue and brown is diluted to lilac or Isabella
219
If you are S+ what happens
No white spots
220
If you are sI what happens
Irish spotting
221
If you are sp what happens
Piebald spotting
222
If you are sw what are you
Extreme white piebald
223
How does spots appear
Chest, Paw, muzzle, tail, extends
224
What does the agouti gene do
Controls pigment distribution. The relative amount and location of dark and light pigment responsible for certain yellow to red coats also responsible for certain coat pattern such as Graywolf coats as well as bi color coats such as tan and saddle
225
If you are As what are you
Solid color
226
If you are ay what are you
All tan or sable
227
If you are a+ what are you
Agouti. Wolf hair. Gray
228
If you are asa what are you
Saddle
229
If you are at what are you
Tan point
230
What is the solid color allele do
Uniform color determined by other genes. Black, brown, blue, Isabella dog with no red pigmentation
231
What does the time or Sable allele do
Pheomelanin pigment varying from yellow to red. Masks effect of being Jean to varying degrees, can still allow for some expression of B Gene. Likely affected by many modifier genes
232
What is the Graywolf type agouti gene
Interact with Gene B. Causes agouti guard hairs
233
What Does the saddle gene do
Creates a dorsal saddle which is black, blue, chocolate, or lilac. With red elsewhere
234
What does the tan point gene do
Makes black, blue, chocolate, or lilac base with red on paws, muzzle and eyebrows
235
What does the E gene do
The melanin distribution Jean. Expression of agouti a gene depends on e.g. that also controls pigment distribution and deposition on coat. E Jean has a recessive mutations that is epistatic on other distribution and colored jeans: ee genotype
236
If you are EBR what are you
Brendel or reverse brindle
237
If you are E what are you
Normal color
238
If you are e what are you
Yellow. No black color possible
239
What happens if Ebr is with As
It won't express. Needs the presence of reds
240
What are three dogs that are ee dogs
Golden retriever, Irish setter, yellow lab
241
What does the I gene do
Dilutes pheomelanin. Does not affect eumelanin (blacks)
242
What does the mask gene do
If Ma then black mask. If na then no black mask
243
What does the m+ gene do
No dilution
244
What does the M gene do
Merle. Heterozygous has blotches of dark color on later diluted background
245
If you are MM what are you
Entirely or almost entirely white. Usually blue Iris, Deaf, partially or totally blind and Sterile
246
What does a ticking gene do
Creates numerous small spots of white and colored hairs on white areas of the coat. Ticking Gene can only exert its effect in the presence of the mutant S allele of white spotted coats
247
If you are tt what are you
Not ticked by coloured hairs
248
What is the F gene
Flecking. It's unique to Dalmatian coats ensures sharp black spots that are all-black rather than a mix of black and white hairs. ff must be accompanied by T
249
What is the G Gene
The graying. Gradual replacement of colored by uncolored hairs causing silvering graying appearance.
250
If yu are g you are
No silverig with age
251
If you are L+ what are you
Short smooth hair
252
If you are l you are
Long hair
253
If you are Wh you are
Wire haired
254
If you are Hr you are
Hairless
255
If you are k you are
Kinky
256
What are three types of breeding used in domestic animals
Line breeding, inbreeding, outbreeding
257
What is inbreeding
Meetings between individuals more closely related than the average relatedness between two individuals chosen at random from the population
258
What does inbreeding result in
Inbreeding modifies genotypic frequencies more specifically it increases homozygosity. The condition in which an animal inherits two identical of alleles for a given gene
259
How does inbreeding increase homozygosity
More of the same alleles in common and mating closely related individuals increases chance for identical alleles to be paired within their offspring
260
What is the closest inbreeding in mammals
Full siblings with both parents in common or mating of a parent to its offspring
261
When does less severe inbreeding occur
Trina half siblings with one parent in common or grandparents and grandchildren uncles and nieces and nephews and aunts and first cousins
262
More closely related the individuals that are mated blank the more blank in blank
The more closely related the individuals that are mated the more rapid the increase in homozygosity.
263
What is special about related individuals
They of one or more ancestors in common
264
What is relatedness
Proportion of alleles identical between two individuals
265
What is the coefficient of relatedness measure
Probability that for any given location randomly selected alleles from both individuals will be identical. In other words the percentage of identical alleles both related individuals have
266
The meeting of related individuals results and what
Inbred offspring. The greater the degree of relatedness between the two individuals, the more inbred the offspring from such a meeting will be.
267
What does the inbreeding coefficient F measure
Measures the probability that the offspring possesses at any given location two identical alleles originating from a given ancestor
268
Inbreeding can lead to a phenomenon known as what
Inbreeding depression. Decrease in performance observed and animals originating from in breadlines. Inbreeding depression generally affects traits associated with natural fitness sedges reproduction viability growth rate disease resistance I can also result from an increased frequency of recessive anomalies
269
In mutt animals what is special about them
They have something called hybrid strength
270
Whats positive about inbreeding?
Helps perpetuate some breed-specific desired traits originating from a small group of animals. Can make a group of animals at all resemble each other from one generation to the next. Can also be used to remove harmful recessive genes and select good recessive traits within a population
271
What Is line breeding
The form of inbreeding. Maintain strong genetic relatedness to specific ancestors of superior quality while minimizing other genetic relationships.
272
What is outbreeding
Meeting of individuals that are less related to each other than the average relatedness between couples breeding at random within a population. While inbreeding increases homozygosity outbreeding increases heterozygosity. It increases heterozygosity because less related the individuals the greater the pop probability that the alleles received by their ancestors are different. Causes hybrid strength
273
What are the three different forms of outbreeding
Outcrossing: between unrelated lines within a breedCrossbreeding: between different breeds Interspecies crosses: between different species
274
What is outcrossing
Meetings between unrelated individuals or between unrelated lines within a breed. Continual inbreeding results in increased inhomogeneity no further improvement with new genes but infusion of new alleles from unrelated lines may help achieve higher performance
275
What is crossbreeding
Meetings between individuals of different breeds. Example cockapoo
276
It is interspecies breeding
Meetings between different species
277
What is the advantage of outbreeding
All in brooding tends to decrease overall fitness outbreeding tends to increase overall fitness. Causes hybrid strength. Overall fitness of offspring of team through outcrossing or crossbreeding superior to fitness of the parents. Increased fitness expressed as improved fertility weight gain resistance to disease and stress
278
What are the most three lethal types of cancer
Long, stomach, liver
279
What are some causes of cancer
Carcinogens, and infections, radiation, we can immune system, hormones
280
What are some inherited forms of cancer
Colon, Breast or ovarian, kidney
281
What are the two ways that balance on normal cell growth can be disrupted
By uncontrolled cell growth or loss of the cells ability to undergo apoptosis. (Cell death)
282
What are some characteristics of cancer cells
There genetically unstable due to loss of DNA repair mechanisms. Defied excessively. Live indefinitely. Lose the normal attachment other cells so that become metastatic which enables them to travel by the blood or lived to invade distant sites. They also secrete signals for angiogenesis which is growth the blood vessels into Tumors
283
What are some characteristics of benign tumors
Are slow-growing, usually surrounded by capsule. Do not invade nearby tissues but can damage organs by compressing them. Begnin tumors generally do not spread by invasion or metastasis
284
What are some characteristics of malignant tumors
Cells divide rapidly therefore tumors grow rapidly. Cells mutate faster. No clear boundaries set legs out in surrounding tissue. Do not perform normal function of tissue. Malignant tumors are capable of spreading by invasion and meta-Stasis
285
What is metastasis
Cells in a primary tumor develop the ability to scape and travel in the blood. Tumor secretes enzymes to break down extracellular matrix and gain access to blood vessels and blood they can escape attacked by me and cells by touching to platelets
286
What is angiogenesis
New blood vessel growth from existing blood vessels. Stimulated by proteins
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Where the two genes responsible for tumorigenic cell growth
Proto-oncogenes and tumor suppressor genes
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What can happen to proto-oncogenes
Become mutated or activated oncogenes that cause malignant transformation
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What can happen to tumor suppressor genes
The loss or mutation of the tumor suppressor genes which can cause malignant transformation
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What are proto-oncogenes and give two examples of them
A proto-oncogene is a normal gene that become an oncogene producing uncle proteins due to mutations or increased expression. Proto-oncogenes code for cellular proteins which regulate normal cell growth and differentiation. Examples other RAS and MYC genes
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What is the RAS gene
Present in human and animal cells. Codes for RAS protein signal cells at appropriate times to divide and grow
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What is the MYC gene
Plays a role in cell cycle progression. Apoptosis and cellular transformation
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How are oncogenes acquired
Virus or mutation in proto-oncogenes
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What are tumors suppressing genes
Tumor suppressor protein stop division of mutated cells until mistakes in DNA are repaired by NZ. Tumor suppressor proteins keep most mutations from being passed on to daughter cells and developing into cancer. If the jeans for tumor suppressing protein mutate the break on cell division is removed and cancers may results
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What are two important tumor suppressing proteins
P 53 protein and the RB protein
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What is the P 53 tumor suppressing gene
Rdean the genome. Prevent so entering SP's repairs DNA and causes apoptosis. Mutations in the P 53 gene I found in more than 50% of cancers. The normal P 53 protein can be inactivated. HPV produces binding protein
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What is the RB gene
If both alleles are mutated early in life it can cause retinoblastoma. The most common malignant tumor of the eye in children
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What are the DNA repair genes
Genes that ensure each strand of genetic information as accurately copied during cell division of the cell cycle. Mutations in DNA repair jeans lead to an increase in the frequency of mutations and other games such as proto-oncogenes and tumor suppressing genes
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This chemotherapy used for
It targets rapidly dividing cells. Used to kill residual cells from primary tumor and for metastasis
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What is immunotherapy used for
Uses the body's own immune system to fight cancer. Using antibodies cancer vaccines or nonspecific immunotherapy
