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Flashcards in Cell Genetics Deck (41)
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1
Q

Define Genetics and Genes

A

Genetics: Study of genes which are the units of inheritance

Genes: a Hereditary unit consisting of a specific sequence of DNA that occupies a specific location on a chromosome

2
Q

Define Chromosome

A

Carrier of genetic Information that present differently in different cell types

3
Q

Define Chromosomal Abnormalities

A

Difference of Chromosomal Structure or Transcription

4
Q

Give three examples of Nondisjunction

A

Down Syndrome (Trimosy 21) Turner Syndrome (X0), Linefelter Syndrome (XXY), Triple X Syndrome

5
Q

Define the difference between Transcription and Translation

A

Translation: copying of a specific genetic sequence to produce the corresponding sequence of mRNA, happens in Nucleus

Transcription: Assembly of a new protein using its amino acid building blocks as specified by the mRNA, occurs in cytoplasm by Ribosomes

6
Q

Homologous

A

Chromosomes of the same kind, same linear sequence of genes, look alike, pair during Mieosis

7
Q

Dipold

A

Two of every general type of chromosome in ordinary blood cells

8
Q

Locus

A

Position of a gene on its chromosome, position on genetic map

9
Q

Centromere

A

region(S) of a chromosome with which the spindle fibers become associated during mitosis and meiosis

10
Q

Telomere

A

The Natural unipolar chromosome ends in eukaryotes, protects the tips from erosion and sticking together

11
Q

Linkage Group

A

Group of gene loci that can be placed in linear order which tends to be inherited together

12
Q

Gametic Number

A

Number of Chromosomes in gametes (egg and Sperm) of an organism, (represented by N)

13
Q

Somatic Number

A

Number of chromosomes in ordindary blood cells of an organism, 2n

14
Q

Chromatin

A

All the Chromosomes together in a dispersed form

15
Q

Heterochromatin

A

Inactive form, condensed

16
Q

Euchromatin

A

Active Form, visible under light microscopy

17
Q

Somatic Cell Divison

A

Process where single somatic cells divide into two daughter cells

18
Q

Mitosis

A

Qualitative and quantitative division of nuclear genetic material

19
Q

Cytokinesis

A

Cytoplasmic Division/Distributes cytoplasmic constituents among the new cells

20
Q

Describe Prophase

A

chromatin fibers condense; nuclear membrane and nucleoli disappear; microtubule organizing center (centrosome) produces mitotic spindle apparatus which elongates and attaches to kinetochores; centrosomes move to opposite poles pushed by lengthening microtubules

21
Q

Describe Metaphase

A

duplicated chromosomes line up on metaphase plate; chromatids parallel equator; spindle microtubules attach to the kinetochores (many connections were already made during prophase)

22
Q

Describe Anaphase

A

centromeres split; chromosomes move apart from each other; cleavage furrow forms

23
Q

Describe Telophase

A

terminal phase; chromosomes have moved as far apart as they are going to; mitotic spindle disappears; chromosomes decondense and unwind into chromatin; cytokinesis occurs; nucleus/nuclear envelope reconstituted; nucleoli reappear

24
Q

The human karyotype must consist of what?

A

22 pairs of autosomes, 1 pair of sex chromosomes

25
Q

What is the function of Meiosis?

A

Reduce Chromosome number to that of body cells
Produce Gametes
Increase viability through crossing over

26
Q

Describe and Tell the Phases of Mitosis

A

Prophase - chromatin fibers condense; nuclear membrane and nucleoli disappear; microtubule organizing center (centrosome) produces mitotic spindle apparatus which elongates and attaches to kinetochores; centrosomes move to opposite poles pushed by lengthening microtubules

Metaphase - duplicated chromosomes line up on metaphase plate; chromatids parallel equator; spindle microtubules attach to the kinetochores (many connections were already made during prophase)

Anaphase - centromeres split; chromosomes move apart from each other; cleavage furrow forms

Telophase - terminal phase; chromosomes have moved as far apart as they are going to; mitotic spindle disappears; chromosomes decondense and unwind into chromatin; cytokinesis occurs; nucleus/nuclear envelope reconstituted; nucleoli reappear

27
Q

Describe Allele

A

One or two or more alternative forms of the same gene, occupy the same locus on a particular chromosome or linkage group

28
Q

What is a De Novo Mutation?

A

New Mutation that was not inherited from either parent

29
Q

What is a mutation>?

A

An inheritable change in DNA, changes nucleuotide sequence of genetic material, mutations give rise to alleles or new genes

30
Q

What is the difference between a Somatic and Germ line mutation?

A

Somatic mutation- not involving reproductive cells and generally transmitted to next generation

Germ Line- Passed to the next generation

31
Q

What is Homozygous?

A

Same allele at specified gene loci in homologous chromosome segments (AA, aa)

32
Q

What is Heterozygous?

A

different alleles at specified gene loci in homologous chromosome segments (Aa or Jk^a Jk^b)

33
Q

What is Hemizygous?

A

genes that are present only once in the genotype; not in the form of pairs of alleles; occurs in haploids, differential segments of sex chromosomes, diploids as result of aneuploidy or loss of chromosome segments

34
Q

What is Genotype and Phenotype?

A

Genotype - genetic makeup of an organism or virus

Phenotype - observable properties or traits of a cell or organism; results from interaction of genotype and environment

35
Q

Carrier (genetic carrier)

A

individual heterozygous for a recessive gene; able to produce offspring with homozygous disease condition

36
Q

What are the parts of Mendelian inheritance

A

Law of Segregation:
gametes are haploid

Law of Independent Assortment: various alleles of given gene that reside in gametes is unaffected by various alleles of other genes)

37
Q

At what chomosome does Blood typing lie on the genetic spectrum?

A

Chromosome 9

38
Q

Describe the 5 blood types and their components

A

‣ A = A antigen present; Anti-B antibody present

‣ B = B antigen present; Anti-A antibody present

‣ AB = Both A and B antigens present; Neither antibody present

‣ O = Neither A nor B antigen present; Both Anti-A and Anti-B antibodies present

Bombay

39
Q

What is the most common cause of Dwarfism?

A

Achondroplashia, 70%, Bone growth disorder

40
Q

Describe the most common cause of albinism?

A

Deficiency in the last step of the pathway wherein tyrosinase acts on tyrosine to produce melanin

41
Q

Punnett Square

A

Assist in to determining Dominent and recessive traits by mathmatical probabilities/ 75% probability of dominent phenotype)