Genetics Workbook Ohb

Front 1

How is hereditary material carried in the human body?

Back 1

chromosomes

Front 2

genes

Back 2

functional units of heredity consisting of DNA sequences that code for specific amino acids and thus for formation of specific proteins

Front 3

chromosomes

Back 3

classified by structure and banding pattern

Front 4

homologous pairs

Back 4

chromosomes common to both sexes

Front 5

alleles

Back 5

alternative form of a gene, one member of a pair

Front 6

homozygous

Back 6

If both alleles are the same, they and the organism are homozygous with respect to that gene.

Front 7

heterozygous

Back 7

When the alleles of a pair are heterozygous, one is dominant and the other is recessive.

Front 8

karyotype

Back 8

number and appearance of chromosomes in the nucleus of a eukaryotic cell

Front 9

crossing over

Back 9

exchange of genetic material between homologous chromosomes that results in recombinant chromosomes

Front 10

phenotype

Back 10

observable physical or biochemical characteristics of an organism

Front 11

genotype

Back 11

genetic makeup of a cell, an organism

Front 12

mitosis

Back 12

leads to the production of two daughter cells identical in chromosome number to the parent cell

Front 13

meiosis

Back 13

leads to the production of four daughter cells, but each containing only half the number of chromosomes of the parent cell

Front 14

single gene-inheritance

Back 14

autosomal, x-linked, complex

Front 15

dominant trait

Back 15

the trait is expressed if the dominant allele is present on at least one of the pair chromosomes

Front 16

recessive trait

Back 16

can be expressed only when the allele responsible for that trait is present on both chromosomes or when the dominant allele is not present

(ex: x-linked genes in the XY male)

Front 17

Why do recessive traits become more common with consanguineous matings?

Back 17

recessive characteristic can only be seen in the children of a heterozygous parent

Front 18

consanguineous

Back 18

between relatives

Front 19

x-linked traits

Back 19

genes on the x chromosome

Front 20

examples of x-linked traits

Back 20

red-green color blindness, hemophilia A, hemophilia B, Duchenne muscular dystrophy, Becker's mescular dystrophy, Coffin-Lowry syndrome, Blue cone monochromacy, Barth syndrome

Front 21

Testicular development of the indifferent gonad occurs regardless of whether viable _______ _______ are present.

Back 21

germ cells

Front 22

However, the germ cells must be present for the ____________ to differentiate.

Back 22

ovaries

Front 23

multifactoral inheritance

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due to the interaction of genetic and environmental factors

Front 24

Multifactoral inheritance includes traits such as __________ and ____.

Back 24

height, BP

Front 25

Multifactoral disorders include birth defts such as

Back 25

neural tube defects, some congenital heart defects, congenital dislocated hips, cleft lip and palate, pyloric stenosis

Front 26

developmental disorder

Back 26

error in meitotic division

Front 27

In the case of formation of gametes with a trisomy or monosomy, one gamete will have 24 chromosomes and the other will have only ____.

Back 27

22

Front 28

Nondisjunction is more likely to occur during the recombination that takes place during the first ___________ division.

Back 28

meiotic

Front 29

trisomy

Back 29

presence of an extra chromosome

Front 30

monosomy

Back 30

one member of a pair of chromosomes is missing

Front 31

mosaicism

Back 31

When mitotic nondisjunction occurs later in development some cell lines have an abnormal number.

Front 32

What are the possible results of non-disjunction of the sex chromosome?

Back 32

Klinefelter syndrome, extra Y chromosome, Tuner syndrome

Front 33

translocation

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occur following breaks in one or more chromosomes, genetic material is transferred from one chromosome to another

Front 34

A balanced translocation occurs when chromosomes exchange pieces and no genetic material is ______.

Back 34

lost

Front 35

If material is gained or lost, that is considered an _________ ___________.

Back 35

unbalanced translocation

Front 36

Those with unbalanced translocations may have multiple __________.

Back 36

anamolies

Front 37

__________ _____________ is due to translocations, most commonly between chromosomes 14 and 21.

Back 37

Down syndrome

Front 38

Depending on which combination of 21 and 14 chromosomes are transferred to the gametes, this individual can produce normal, carrier, monosomic, or _________ offspring.

Back 38

trisomic

Front 39

Down syndrome is due to _______________, most commonly between chromosomes 14 and 21.

Back 39

translocations