Inheritance, Variation And Evolution Flashcards
1
Q
What is asexual reproduction?
A
The PRODUCTION of OFFSPRING which does NOT INVOLVE the FUSION of GAMETES from TWO DIFFERENT PARENTS
2
Q
Why does genetic material not mix in asexual reproduction?
A
There is NO FUSION of GAMETES
3
Q
What are some examples of organisms which reproduce using asexual reproduction?
**
A
-Bacteria
-Some plants such as strawberries
-Spores
-Potato tubers
-Daffodil bulbs
4
Q
What process does asexual reproduction use to create identical copies?
A
Mitosis
5
Q
Describe each stage of the Mitosis Cell Cycle
(BLURT)
A
6
Q
What is the definition of sexual reproduction?
A
The FORMATION of a NEW ORGANISM by COMBINING the GENETIC MATERIAL of TWO other ORGANISMS
7
Q
What IS a gamete?
**
A
A sex cell
8
Q
What happens to the male and female gametes during sexual reproduction?
A
The NUCLEI of the MALE and FEMALE GAMETES are FUSED in order to CREATE a ZYGOTE
9
Q
What is the product of sexual fertilisation?
**
A
A FERTILISED EGG cell, otherwise known as a ZYGOTE
10
Q
What is a chromosome?
A
11
Q
How are chromosomes distributed between parents?
**
A
Each GAMETE contains HALF the NUMBER of CHROMOSOMES in each HAPLOID
12
Q
What is the full complement of chromosomes called?
**
A
A Diploid
13
Q
What is the difference between a zygote and an embryo?
A
An EMBRYO is a DEVELOPING ORGANISM that forms after the ZYGOTE has DIVIDED and GROWN through MITOSIS
14
Q
What are the gametes in animals?
**
A
Sperm and Eggs
15
Q
What are the gametes in flowering plants?
**
A
Pollen and eggs
16
Q
Why are offspring produced by sexual reproduction different to each other?
A
Offspring are DIFFERENT because they inherit RANDOM COMBINATION of GENES from BOTH parents.
17
Q
Why are offspring produced by sexual reproduction different to their parents?
**
A
GAMETES from BOTH PARENTS FUSE and PARENTS are NOT GENETICALLY IDENTICAL
18
Q
What process does sexual reproduction use?
A
Meiosis
19
Q
What is Meiosis?
A
MEIOSIS is CELL DIVISION producing FOUR GENETICALLY UNIQUE HAPLOID cells.
20
Q
Describe the four stages of Meiosis
(BLURT QUESTION)
A
21
Q
What is the difference between mitosis and meiosis?
(BLURT QUESTION)
A
22
Q
Describe the full process of sexual fertilisation with reference to meiosis
(BLURT QUESTION)
A
23
Q
By what process do the number of embryonic cells increase?
A
Mitosis
24
Q
What happens to cells during embryonic development other than that they multiply?
A
Differentiation
25
What is the genetic material in the nucleus made up of?
***
DNA
26
What is DNA?
***
A LARGE and COMPLEX MOLECULE which MAKEA UP ALL of the GENETIC MATERIAL in the NUCLEUS
27
What is the structure of DNA?
**
A double helix
28
What does DNA carry?
***
The GENETIC CODE
29
What is a genetic bar code?
***
The DIFFERENT GENETIC CODES which are FORMED from PERSON to PERSON since DNA can be SEPARATED and REARRANGED
30
Write a flow diagram showing the sizes of DNA, Chromosomes and Genes from smallest to biggest
***
(BLURT QUESTION)
31
Why is each individual gene important?
**
Each INDIVIDUAL GENE CODES for a SPECIFIC CHARACTERISTIC
32
What are genes the unit of?
***
Hereditary
33
What is heredity?
***
The PASSING DOWN of TRAITS and CHARACTERISTICS from the GENETIC MATERIAL of TWO PARENTS to their OFFSPRING
34
35
What is a genome?
The ENTIRE GENETIC MATERIAL of an ORGANISM
36
37
What is one reason why fully understanding the human genome is useful to scientists?
**
-Enables scientists to TRACE HUMAN MIGRATION PATTERNS from the PAST
-Enables scientists to UNDERSTAND INHERITED DISORDERS and hence their TREATMENT
-Enables scientists to SEARCH for GENES which are LINKED to DIFFERENT TYPES of DISEASES
38
How does fully understanding the human genome trace migration patterns from the past?
***
39
How does fully understanding the human genome help to understand inherited disorders and their treatment?
***
40
How does fully understanding the human genome help to trace migration patterns from the past?
***
41
How does fully understanding the human genome help to understand inherited disorders and their treatment?
***
42
How does fully understanding the human genome help to search for genes linked to different types of diseases?
***
43
What are scientists currently looking for in relation to genes?
**
DISEASE associated GENES
44
What is an example of a disease which can be caused by genes?
Breast Cancer
45
Why are some diseases hereditary?
***
MUTATIONS in GENES can lead to OFFSPRING INHERITING these if they EXIST in the PARENTS GAMETES
46
What makes some diseases not hereditary and others hereditary?
***
-Not all DISEASES are caused by a MUTATION in GENES which are then PASSED DOWN through the GENES MUTATING in GAMETES
-Lots of diseases are CAUSED by ENVIRONMENTAL FACTORS
-Some DISEASES can be CAUSED or ONSET by EITHER ENVIRONMENT and/or GENETIC FACTORS
47
What is a pedigree analysis?
***
A DIAGRAM which shows the INHERITANCE PATTERN of the DISEASE which is TO BE DETERMINED
48
What has the pedigree analysis enables scientists to do?
***
IDENTIFY the DIFFERENCES between AFFECTED and UNAFFECTED INDIVIDUALS which is USEFUL for MEDICAL RESEARCH
49
How are genetic diseases detected currently?
***
Blood tests
50
What is one example of a genetic disease?
**
Cystic fibrosis
51
What is one example of a treatment of a genetic disease?
***
52
Why is the treatment effective?
***
53
What is the difference between the gamete and genome?
**
A GAMETE is a SEX CELL which contains HALF of the OFFSPRINGS CHROMOSOMES. The GENOME is ALL of the GENETIC MATERIAL in an ORGANISM, it is the FULL SET of DNA.
54
Why isn’t everyone’s DNA unique?
Identical twins have the EXACT same DNA
55
Why do identical twins have the same DNA?
***
56
What are chromosomes (again) ?
***
CHROMOSOMES are MADE UP of LONG THREADS of DNA which are MADE UP of MANY GENES
57
What is a gene?
***
58
What do genes do?
**
59
Why are genes important in reproduction?
**
GENES are the UNITED STATES of HEREDITARY and may be PASSED DOWN throughout GENERATIONS
60
What are two examples of characteristics controlled by a single gene?
***
-Fur in animals
-Red-green colour blindness in humans
61
Why do some characteristics only need one gene?
***
62
What is meant by different forms of a gene?
***
There are DIFFERENT VERSIONS of the SAME GENE. For example, the GENE for EYE COLOUR has an ALLELE for BLUE EYE COLOUR and an ALLELE for BROWN EYE COLOUR
63
What are different forms of a gene called?
Alleles
64
Why are alleles necessary for certain characteristics rather than single genes?
***
65
Where are genes located in two chromosomes?
***
66
What is homozygous?
**
A GENOTYPE where the ALLELES are IDENTICAL for the SAME CHARACTERISTIC
67
What is heterozygous?
**
ALLELES are both DIFFERENT for the SAME CHARACTERISTIC
68
Why are some genes homozygous and some are heterozygous?
***
69
What is a genotype?
***
The ALLELES that a an organism has for a PARTICULAR CHARACTERISTIC
70
What is a phenotype?
**
The VISIBLE CHARACTERISTICS of an ORGANISM that RESULT from its GENOTYPE
71
What is meant by a dominant allele?
**
An ALLELE which is ALWAYS EXPRESSED even if only ONE COPY is PRESENT
72
What is meant by a recessive allele?
**
An ALLELE which is ONLY EXPRESSED if the INDIVIDUAL has TWO COPIES and does NOT HAVE the DOMINANT ALLELE of that GENE
73
What makes an allele dominant?
***
74
What makes an allele recessive?
**
75
What is meant by ‘a dominant allele is always expressed’?
As long as the organism has ONE COPY of the ALLELE it will always DETERMINE a CHARACTERISTIC
76
What are dominant alleles represented by?
Capital letters
77
How many copies of a dominant allele do you need to inherit that allele’s characteristic?
One
78
When is a recessive allele expressed?
When there is NO DOMINANT ALLELE for the SAME GENE and TWO COPIES of the SAME ALLELE
79
Why are recessive alleles not always expressed?
DOMINANT ALLELES are ALWAYS EXPRESSED over RECESSIVE ALLELES
80
What are recessive alleles represented by?
Lower-case letters
81
How many copies of a recessive allele do you need to inherit that allele’s characteristic?
Two
82
Where are allele’s found?
83
Where are allele’s produced?
84
Why are most characteristics a result of multiple genes interacting?
***
85
What is monohybrid inheritance?
***
The INHERITANCE of ONE TRAIT by ONE GENE and TWO DIFFERENT ALLELES
86
What does a Punnet Square show?
The DIFFERENT POSSIBLE COMBINATIONS of ALLELES
87
What does a Punnet Square show?
***
The PROBABILITY a CERTAIN ALLELE PAIR is INHERITED
88
Why is probability used to predict allele combinations?
**
INHERITANCE is a RANDOM PROCESS
89
What is a genetic cross?
90
How do you draw a Genetic Cross?
(BLURT QUESTION)
91
What do two capital alleles show?
**
Homozygous DOMINANT
92
What do two lowercase alleles show?
**
Homozygous RECESSIVE
93
What does one upper case and one lower case allele show?
Heterozygous DOMINANT RECESSIVE
94
How many pairs of chromosomes are in the nucleus?
Two
95
What are autosomes?
***
THE TWENTY TWO PAIRS which DO NOT CONTROL SEX CHARACTERISTICS
96
How many pairs of chromosomes determine sex?
**
One pair
97
What sex chromosomes are found in men?
**
X and Y
98
What sex chromosomes are found in women?
**
X and X
99
Why do men and women have different chromosomes?
***
100
What is a human karyotype?
***
A DIAGRAM used to SHOW all of an ORGANISMS CHROMOSOMES in PAIRS
101
How do you read a human karyotype?
**
In WOMEN, the RED BOX shows the SEX CHROMOSOMES XX
-In MEN, the BLUE BOX shows the SEX CHROMOSOMES XY
102
Restate the definition of a zygote
**
A FERTILISED EGG CELL
103
On average what is the ratio of male to female offspring?
**
1:1
104
Why aren’t all babies female?
***
105
What is cystic fibrosis?
***
An INHERITED DISORDER of CELL MEMBRANES that MAINLY AFFECTS the LUNGS and the DIGESTIVE SYSTEM
106
What happens to the lungs when someone has cystic fibrosis?
The LUNGS become CLOGGED as lots of EXCESS MUCUS is PRODUCED
107
How do the conditions of the lungs change over time for those with cystic fibrosis?
The LUNGS become INCREASINGLY DAMAGED and eventually STOP WORKING
108
Why is life expectancy reduced with cystic fibrosis?
The LUNGS eventually STOP WORKING
109
What is cystic fibrosis caused by?
A FAULTY RECESSIVE Allele
110
What has to happen for a child to be born with cystic fibrosis?
The child needs to have HOMOZYGOUS RECESSIVE ALLELES
111
Why do parents of children with cystic fibrosis usually not have the condition?
PARENTS are usually HETEROZYGOUS with the RECESSIVE ALLELE but are not usually HOMOZYGOUS with the FAULTY ALLELE
112
What will happen to a homozygous individual with the recessive allele?
They will contract CYSTIC FIBROSIS
113
Why will the homozygous person with the recessive allele develop cystic fibrosis?
***
114
What will happen to the heterozygous person with the recessive allele?
They will CARRY the FAULTY GENE but will NOT CARRY the DISEASE
115
Why will the heterozygous person with the recessive allele not develop cystic fibrosis?
They carry ONE FAULTY GENE and ONE that WORKS NORMALLY
116
What will happen if someone is homozygous with the dominant allele?
They will NOT DEVELOP CYSTIC FIBROSIS at all
117
Why will the homozygous person with the dominant allele not develop cystic fibrosis?
You need TWO FAULTY ALLELES for the CONDITION
118
What is a faulty allele?
***
119
What makes an allele faulty?
***
120
Draw a punnet square for two heterozygous parents, Ff and use it to estimate the probability the child is born with cystic fibrosis
**
121
Draw a punnet square for a father with two recessive allele and a mother with two dominant alleles and use it to estimate the probability the child is born with cystic fibrosis
**
122
What is polydactyly?
An INHERITED CONDITION where a PERSON has EXTRA FINGERS or TOES
123
What is polydactyly caused by?
Caused by a DOMINANT ALLELE GENE
124
Why can polydactyly be passed on?
It is GENETIC
125
Who will inherit polydactyly?
The future OFFSPRING from just ONE PARENT ALLELE
126
What is the probability of offspring having polydactyly?
1:1
127
Draw a genetic cross of a generated mother and father type of alleles to show sex inheritance
128
What is genetic testing?
An ANALYSIS of a PERSON’S DNA to see if they CARRY any ALLELES which can CAUSE GENETIC DISORDERS
129
At what stage of a persons life can genetic testing be done?
Any stage
130
What is antenatal testing?
A type of GENETIC TESTING used to ANALYSE an INDIVIDUALS DNA or CHROMOSOMES BEFORE they are BORN
->blood test and ultrasound during first trimester to assess risk of chromatic disorders
131
Who is antenatal testing offered to?
Couples who may have an INCREASED RISK of PRODUCING a BABY with an INHERITED DISORDER
132
What are the limitations of antenatal testing?
It CANNOT DETECT ALL the RISKS of INHERITED DISORDERS
133
What is neonatal testing?
The ANALYSIS of a BLOOD SAMPLE taken from a BABY’S HEEL
134
What is neonatal testing also known as?
The new born blood spot test
135
What is Pre-implantation genetic diagnosis used for?
It is used to test for GENETIC VARIANTS which could CAUSE DISEASE
136
What is the process of pre-implantation genetic diagnosis?
-IVF
-Once the EMBRYOS have REACHED the EIGHTH CELL STAGE, ONE CELL is REMOVED from EACH EMBRYO
-the CELLS are TESTED for the DISORDER-CAUSING ALLELES
-EMBRYOS that DON’T CONTAIN the DISORDER ALLELES are IMPLANTED into the UTERUS
137
What is the significance of the eighth cell stage in embryos?
There is SUFFICIENT GENETIC MATERIAL
138
What are some economic issues of embryo screening?
EXPENSIVE so there is a DIVIDE in ACCESS to GENETIC TESTING and TREATMENT in NON-NHS COUNTRIES or where INSURANCE is not SUFFICIENT
139
What are some social issues with embryo screening?
INEQUALITY in ACCESS
Fear of DESIGNER BABIES where GENETIC MODIFICATION OCCURS
which INTENSIFIES SOCIAL STRATIFICATION
140
What are some ethical issues with embryonic stem screening?
DISCARDING EMBRYOS could be seen as DESTROYING or UNDERMINING the VALUE of LIFE
The POTENTIAL RESULTANT DISCRIMINATION of REDUCING HUMAN BEINGS to their GENETIC MAKEUP
141
Why are genetic tests not available for every inherited disorder?
***
142
What is another limitation of genetic testing?
**
Genetic tests are NOT COMPLETELY RELIABLE
143
What is a false positive?
***
A GENETIC TEST that WRONGLY DETECTED a FALSE POSITIVE
144
What is a consequence of a false positive?
Unnecessary STRESS / TREATMENT
145
What is a false negative?
A GENETIC TEST that has FAILED to DETECT a FAULTY ALLELE or CHROMOSOME
146
What is a consequence of a false negative?
The parents may be WRONGLY REASSURED. These results can have a MAJOR IMPACT on the lives of individuals, through PREGNANCY TERMINATION, FUTURE DECISIONS and PLANNING the LEVEL of CARE needed for CHILDREN with INHERITED DISORDERS
147
What is gene therapy?
The INSERTION of COPIES of a NORMAL ALLELE into the CHROMOSOMES of an INDIVIDUAL who CARRIES a FAULTY ALLELE
148
What is a limitation of gene therapy?
It is NOT ALWAYS SUCCESSFUL
149
Describe all four stages of gene therapy
(BLURT QUESTION)
***
1. IDENTIFY the GENE INVOLVED in the GENETIC DISORDER
2. RESTRICTION ENZYMES CUT OUT the NORMAL ALLELE
3. MULTIPLE COPIES of the ALLELE are MADE
4. COPIES of the NORMAL WORKING ALLELE are INSERTED unto the CELLS of the PERSON who has the GENETIC DISORDER due to a MUTATED or FAULTY COPY of an ALLELE
150
What is one problem with gene therapy?
-The ALLELES may NOT GO into EVERY TARGET CELL which are CELLS that NEED the NEW NON-FAULTY CELL
151
What is another problem with gene therapy?
Some TREATED CELLS may be REPLACED NATURALLY by the PATIENT’S OWN TREATED CELLS as CELLS are FREQUENTLY REPLACED during MITOSIS
152
What is a another problem with gene therapy?
The ALLELES may be INSERTED into the CHROMOSOMES in RANDOM PLACES, rather than in the REQUIRED POSITION, so they DO NOT WORK PROPERLY
153
What is one way to get the alleles into patients cells?
Using NOSE SPRAYS which allow the patient to INTRODUCE the WORKING ALLELE UP their NOSE and it will be TAKEN IN by the BODY and INCORPORATED
154
What is another way to get into allele into patients cells?
Using COLD VIRUSES that are MODIFIED to CARRY the ALLELE, these VIRUSES go into CELLS and INFECT THEM
155
What is another way to get the alleles into patients cells?
The DIRECT INJECTION of DNA
156
What is an ethical issue associated with gene therapy?
The IDEA that GENE ALTERATION is UNNATURAL
157
What is an economic issue with gene therapy?
158
What is a social issue with gene therapy?
159
What is a generational limitation of gene therapy?
160
How can a pedigree analysis chart be used to work out the chance that someone in a family will inherit a disease?
161
What do circles represent in a pedigree diagram represent?
162
What do squares in a pedigree analysis represent?
163
What do coloured in shapes in a pedigree diagram show?
164
What do red shapes show?
165
What do horizontal lines between males and females show?
166
How can pedigree diagrams be used to show the probability of an individual inheriting a genetic disorder?
167
Ask AI to draw a pedigree analysis.
Draw draw a punnet square to estimate the probability
168
Why are individuals within a population usually similar but not identical?
169
What is variation?
The DIFFERENCES in CHARACTERISTICS or TRAITS within a SPECIES
170
What two factors within a species is variation caused by?
-Genetic
-Environmental
171
What factors employ both environmental and genetic factors?
172
Describe the process of genetic fusion during sexual production in humans
(BLURT QUESTION)
173
What are some examples of genetic variation in humans?
174
How can a child’s sex be estimated using the parents’ genotype and a punnet square?
175
What are some environmental causes of variation?
176
What are some environmental examples of variation?
177
What are some examples of a blend of genetic and environmental causes of variation?
178
Why is extensive genetic variation contained within any species?
179
What does variation in genes lead to?
180
How can you tell if genetic variation has taken place?
181
How does environmental variation link to different phenotypes?
182
What is a mutation?
183
How is genetic variation created?
184
Why does most variation not lead to changes in phenotype?
185
What do changes in the phenotype of an organism allow for?
186
What is natural selection?
187
If a change in phenotype proves useful, what happens to the genes?
188
What is the process where genes which have undergone variation resulting in changes in phenotype are passed on through generations?
189
What is the difference between natural selection and evolution?
190
What is the difference between natural selection and variation?
191
Who came up with the idea of evolution?
192
What is an example of adaptation in animals?
(BLURT QUESTION)
193
What is selective breeding?
194
What are the four stages of selective breeding?
(BLURT QUESTION)
195
What are some examples of animals involved in selective breeding?
196
Why do farmers selectively breed cows?
197
What are some examples of useful plant characteristics?
198
What are some examples of desired characteristics in animals?
199
How does selective breeding reduce variation?
200
What is a gene pool?
201
Why does the risk of inbreeding increase with selective breeding?
202
How does inbreeding lead to a reduced gene pool?
203
What are some consequences of a reduced gene pool?
204
What are some benefits of selective breeding?
205
What are some risks of genetic breeding?
206
What are some ethical issues with selective breeding?
207
What is genetic engineering?
208
Describe the main steps of genetic engineering
(BLURT QUESTION)
1. ENZYMES are used to ISOLATE the REQUIRED GENE. This GENE is then INSERTED into a VECTOR such as a BACTERIAL PLASMID or a VIRUS
2. The VECTOR INSERTS the GENE into the REQUIRED CELLS
3. The GENES are TRANSFERRED to ANIMAL, PLANT or MICROORGANISM CELLS during EARLY DEVELOPMENT which ALLOWS them to DEVELOP with the DESIRED CHARACTERISTICS
209
What are GM crops?
210
Why do farmers grow GM crops?
211
What is the main benefit
of GM crops in terms of production and demand?
212
What is yield?
213
Why do GM crops show increased yields?
214
How do GM crops affect populations of wild insects?
215
How do GM crops affect insects?
216
What are some social issues with GM crops?
217
How has bacteria been genetically engineered?
218
Describe the production of insulin in terms of genetic engineering
(BLURT QUESTION)
219
What can genetic engineering help modern medicine?
220
What are some benefits of genetic engineering?
221
What are some risks of genetic engineering?
222
How could genetic engineering help to cure cystic fibrosis?
223
What is the basic idea behind the theory of evolution?
224
How old is the earth?
225
How long ago did life start to form on earth?
226
What was the first bacteria?
227
How long ago did Archean Eons begin to form?
228
What were the first eukaryotes?
229
Why are two reasons why scientists cannot be certain about how life began on earth?
230
Why were many early forms of life soft bodied?
231
Why can evolution occur if only genetic variation and not environment variation can be passed to the next generation?
232
Summarise the key points of the process of natural selection in evolution
(BLURT QUESTION)
233
What is an example of natural selection?
(BLURT QUESTION)
234
What is a fossil?
235
Where are fossils found?
236
What is one thing fossils can be formed from and why?
237
What is another thing fossils can be formed from and why?
238
What is a final thing fossils can be formed from and why?
239
Where are ammonite fossils sourced from?
240
How does the complexity of a fossil link to the age of a rock?
241
How is evolution linked to this link between rock age and organism complexity?
242
Where does evidence for early forms of life come from?
243
What can scientists learn from fossils?
244
What are evolutionary trees?
245
Draw an evolutionary tree for chimpanzees according to evolution
(BLURT QUESTION)
246
Under what conditions are fossils created?
247
Under what conditions are fossils not created?
248
Why are some dead organisms preserved in different ways to fossilisation?
249
What are different ways dead organisms and plants can be preserved?
250
What qualities a material able to preserve dead organisms?
251
What is an example of a peat bog?
252
How do preservations of corpses and other dead organisms help scientists?
253
Why can bacteria evolve?
254
Why can bacteria evolve quickly?
255
What might bacteria become due to evolution?
256
What are the main stages in the development of resistance?
(BLURT QUESTION)
257
Why has the number of resistant strains increased?
258
What is MRSA?
259
What are three ways the rate of development of antibiotic strains can be reduced?
(BLURT QUESTION)
260
Why has antibiotic research slowed?
261
When does extinction occur?
262
What happens during extinction?
263
What are three reasons for extinction?
264
What is speciation?
265
Who came up with the Linnaean system of classification?
266
When was the Linnaean system of classification invented?
267
Why was the Linnaean system of classification invented?
268
What is meant by a ‘kingdom’?
269
What are the five kingdoms?
270
What is meant by ‘phylum’?
271
What are some examples of Phylum?
272
What is meant by ‘class’?
273
What are some examples of
class?
274
What is meant by ‘order’?
275
What is an example of order?
276
What is meant by genus?
277
What is an example of genus?
278
What is meant by ‘species’?
279
What is an example of species?
280
What is a mnemonic to memorise the order of the Linnaean system?
281
What is the binomial system?
282
Why is the binomial system important?
283
Why was the Linnaean system adapted?
284
How has the Linnaean system been developed?
285
