AOS 1 - How is Inheritance Explained? Flashcards
1
Q
What is Accuracy?
A
Relates to how close the data is to the ‘true’ value.
2
Q
What is Precision?
A
Relates to how closely the data agrees with each other.
3
Q
What is Repeatability?
A
Being able to repeat the experiment in the same conditions.
4
Q
What is Reproducability?
A
Whether or not the experiment can be repeated with similar results.
5
Q
What is the ‘True Value’?
A
The value, or range of values, that would be found if the quantity could be measured perfectly.
6
Q
What is Validity?
A
- When it measures what it is supposed to be measuring
- If it has only one Independent Variable.
7
Q
What are Personal Errors?
A
Mistakes or Miscalculations
8
Q
What are Random Errors?
A
Affect the Precision of Measurements - Unpredictable
9
Q
What are Systematic Errors?
A
Affect the Accuracy of Measurements - Differ from true value
10
Q
What are Significant Figures?
A
i.e. 12.034 = 5 Significant Figures whilst 12. 340 = Only. 4
11
Q
What are Chromosomes?
A
Chromosomes carry a large number of genes and contain a molecule of DNA and proteins. They are found in the nucleus of a cell.
12
Q
What is a Eukaryotic cell?
A
Contains a Nucleus.
13
Q
What does Condense mean?
A
To become visible.
14
Q
What do Eukaryotic cells contain?
A
DNA and Histones (Protein)
15
Q
What is condensed DNA called?
A
Chromatin
16
Q
What is a Prokaryotic cell?
A
Has no Nucleus
17
Q
Where are Prokaryotic cells located?
A
Cytosol
18
Q
What does DNA Stand for?
A
Deoxyribonucleic Acid
19
Q
What does each Nucleotide contain?
A
Sugar (Deoxyribose), Phosphate and a Base.
20
Q
What are the 4 different Nitrogenous pairs (Bases)?
A
Adenine\
Complementary Base Pairing
Thymine/
Cytosine\
Complementary Base Pairing
Guanine/
21
Q
How do you draw a DNA molecule?
A
O - Phosphate
\ _ _
\ / \___|| - Base
\ _ / - Deoxyribose Sugar
22
Q
What are Alleles?
A
Variations of a Gene
23
Q
What does an Allele do?
A
They code for specific traits.
24
Q
What does the Female Sex Chromosome look like?
A
X X | | | | | | | |
25
What does the Male Sex Chromosome look like?
```
X Y
| |
| |
|
|
```
26
What is the Genome?
The sum of all organisms DNA
27
How is the Genome determined?
Using the Haploid number of base pairs in an organism
28
How many base pairs do humans have?
3,234,830,000
29
What is the study of Genomes called?
Genomics
30
What is a Homologous Chromosome?
Same Chromosome
31
What does Locus stand for?
Location of Gene on Chromosome - Homologous chromosomes have the same gene at the same Locus
32
What are Autosomes?
Not Sex Chromosomes
33
How many Autosomes are in a human?
22 matched pairs
34
How many genes are in x and y chromosomes?
X = approx. 800. Y = approx. 50
35
Why is the Y chromosome important?
It determines Sex
36
What is the SRY gene?
Found on Y chromosomes and codes for protein controlling development for male characteristics.
37
What sex chromosomes do Birds and Reptiles have?
WZ/ZZ system
38
What pair of sex chromosomes do male birds & reptiles have?
ZZ
39
What pair of sex chromosomes do female birds & reptiles have?
WZ
40
With Birds and Reptiles, who determines the sex?
Female
41
With Humans, who determines the sex?
Male
42
What is Environmental Sex Determination?
When the incubation temperature of the egg determines the sex.
43
How can chromosomes be classified?
By the position of the Centromere
44
What does Metacentric mean?
Middle of Chromosome - Centromere location
45
What does Submetacentric mean?
Towards on end of Chromosome - Centromere location
46
What does Acrocentric mean?
Very close to one end of Chromosome - Centromere location
47
What does Telocentric mean?
Tip of Chromosome - Centromere location
48
What does the size of the chromosome mean?
How many genes it contains - Bigger = More genes
49
What is a Karyotype?
Chromosomes arranged into homologous pairs by their size and centromere position
50
What is an advantage of Karyotypes?
Abnormalities can be identified quickly.
51
What does congenital mean?
Affect offspring.
52
What do changes in chromosomes include?
- Number of Chromosomes
- Change in a part of a Chromosome
- Change in the arrangement of Chromosomes
53
What is Trisomy?
When there are 3 copies of a Chromosome instead of 2.
54
What is an example of Trisomy?
Down Syndrome - Trisomy on Chromosome 21
55
What is Monomy?
When there is only 1 Chromosome of the pair present
56
What is the result of Monomy?
Embryonic death (Unless the sex chromosome is the one affected)
57
What is a Gemete?
Sex Cell
58
When can Errors in sex chromosomes occur?
During Meiosis resulting in a gamete lacking a copy of a chromosome or having an extra one.
59
What is Duplication?
When part of a chromosome is duplicated
60
What is Deletion?
When part of a chromosome is deleted.
61
What is Translocation?
When the location of a chromosome segment is altered and relocated to a new region - Can occur in Down syndrome where part of chromosome 21 attaches to chromosome 14.
62
What is Haploid?
Half the Chromosomes i.e. 23 instead of 46 (Humans)
63
What is Diploid?
Full set of Chromosomes i.e. 46 (Humans)
64
How are Haploid Gametes produced?
Meiosis
65
What are Haploid gametes created by meiosis often called?
Daughter cells haploid
66
What does Meiosis produce?
Variation through crossing over and independent assortment.
67
What is Interphase?
Where DNA replicates (Not a part of Meiosis however must occur for process to start)
68
What is Prophase I?
- Chromosomes Condence
- Nuclear Membrane breaks down
- Crossing Over Occurs
- Homologous Chromosomes pair.
69
What is Metaphase I?
- Homologous Chromosomes line up in the middle
| - Spindle Fibres attach to centromeres
70
What is Anaphase I?
Homologous Chromosomes Segregate (Pulled apart by Spindle Fibres)
71
What is Telophase I?
- 2 Nuclei are formed
72
What is Cytokenisis?
- Cytoplasm Division (Not a part of Meiosis)
73
What is Prophase II?
- Nuclear Membrane breaks down
74
What is Metaphase II?
- Chromosomes line up in the middle
75
What is Anaphase II?
- Sister Chromatids are pulled apart
76
What is Telophase II?
- 2 Nuclei per cell are formed
77
What is Cytokenisis?
- Cytoplasm is divided
- 4 daughter cells that are haploid & genetically different are formed
(Not a part of Meiosis)
78
How can Repeatability be improved?
Make sure the method is specific.
79
How can Reproducibility be improved?
Have a specific method and use appropriate equipment
80
How can Precision be improved?
- Using equipment which record data more precisely
| - Measure quantitative data rather than qualitative data
81
How can Accuracy be improved?
- Select and use appropriate equipment
| - Calibrate instruments
82
How can Validity be improved?
- Incorporate suitable equipment
- All controlled variables are kept constant
- Appropriate measuring procedures are included in the method
- Only having 1 I.V.
83
How can Personal Errors be eliminated?
Personal errors can be eliminated by performing the experiment again correctly the next time, and do not form part of error analysis.
84
How can Systematic Errors be eliminated?
- Calibrating equipment before use.
| - Using appropriate equipment.
85
How can Random Errors be eliminated?
The effect of random errors can be reduced by making more or repeated measurements and calculating a new mean and/or by refining the measurement method or technique.
86
What are Outliers?
Outliers are readings that lie a long way from other results.
87
What do you do about Outliers?
Outliers must be further analysed and accounted for, rather than being automatically dismissed
88
What is Uncertainty?
The uncertainty of the result of a measurement reflects the lack of exact knowledge of the value of the quantity being measured.
89
What are Limitations?
Stops the experiment from getting the correct results.
90
What is a Cross?
The breading of 2 parents to get the genotype of the offspring.
91
What is True Breeding?
Homozygous!!!
92
What is Hybrid?
Offspring of parents that differ in genetically determined traits - Heterozygous
93
Autosomal Dominance?
Where both males and females can be affected, have at least one affected parent and heterozygous express the trait
94
Autosomal Co-dominance?
Where 2 dominant alleles from an autosomal trait both contribute to the phenotype
95
Sex Linked?
Where a gene is located on a sex chromosome
96
X-Linked Recessive
- More Males affected
97
X-Linked Dominant
- More Females
98
Y-Linked
- Only Males affected
| - Affected father always passes it on to sons
99
What is a Test Cross?
A method used to determine the genotype of an organism with a dominant phenotype - Must cross with a homozygous recessive.
100
What is DNA?
Deoxyribonucleic acid - Contains the genetic instructions
101
What is Hereditary?
Genetically transmittable from parent to offspring
102
What are Genes?
A specific sequence of nitrogenous bases that code for a specific trait
103
What is a Nucleotide?
The basic building blocks creating a complex molecule
104
What is Complementary Base Pairing?
Adenine --> Thymine
| Cytosine --> Guanine
105
Why is DNA antiparallel?
So that the Nitrogenous bases can have complementary base pairings.
106
What is a Chromosome?
A thread-like structure that contains DNA and Proteins
107
What is the Centromere?
The location on a chromosome where the spindle fibres attach.
108
What are Histones?
Small proteins
109
What does Ploidy mean?
Number of complete sets of chromosomes i.e. Humans = 23
110
What is a Karyotype?
A view of all organism's chromosomes
111
What are 2 things a Karyotype allows scientists to identify?
1. Gender
| 2. Any abnormalities
