Genetics Review_Tobin2º

Front 1

The Austrian monk whose experiments with pea plants were the beginning of our understanding of genetics was _____________________.

Back 1

Gregor Mendel

Front 2

The different alternatives or choices for a gene (like blue, green, or brown eyes) are called _____________.

Back 2

alleles

Front 3

Crossing organisms from the F1 generation produces the _____ generation.

Back 3

F2

Front 4

Crossing organisms from the P1 generation produces the _____ generation.

Back 4

F1

Front 5

Mendel’s “factors” are now called ___________________.

Back 5

genes

Front 6

Self-pollination produces seeds with genetic information from _______ parent plant(s).

Back 6

ONE

Front 7

What pattern did Mendel see when crossing pure TALL with pure SHORT pea plants?

Back 7

ALL the F1 offspring were tall, but 25% the F2 generation were short and 75% were tall.

Front 8

If a dominant allele is present, the __________________ won’t be seen.

Back 8

recessive allele

Front 9

Pollen is produced by the _________________ part of the flower.

Back 9

male

Front 10

Dominant alleles are represented by a _______ case letter.

Back 10

upper

Front 11

Mendel’s Law of ____________ ____________ explains why alleles end up in different gametes following meiosis.

Back 11

independent assortment

Front 12

_______________________ A characteristic that can be observed such as hair color, seed shape, flower color, etc

Back 12

Trait

Front 13

_______________________ The joining of a sperm and egg to make a zygote

Back 13

fertilization

Front 14

_______________________ A gene choice that MASKS ANOTHER choice for a trait

Back 14

dominant

Front 15

_______________________ A gene choice that IS MASKED BY ANOTHER choice for a trait

Back 15

recessive

Front 16

_______________________ the branch of biology that studies how characteristics are transmitted from parent to offspring

Back 16

genetics

Front 17

_______________________ the passing of characteristics from parent to offspring

Back 17

heredity

Front 18

_______________________ An alternative choice for a gene (such as brown, green, or blue eyes)

Back 18

allele

Front 19

_______________________ An organism that always produces offspring identical to itself if self pollinated

Back 19

pure breeding

Front 20

What is the genotype of a HETEROZYGOUS YELLOW plant? ______________________

Back 20

Yy

Front 21

What is the genotype of A HOMOZYGOUS GREEN SEED plant? ______________________

Back 21

yy

Front 22

Make a cross between a PURE YELLOW SEED parent and a PURE GREEN SEED parent.

Genotypes of Parents: __________ X __________

Back 22

YY x yy

Front 23

POSSIBLE OFFSPRING OF CROSS BETWEEN TWO HOMOLOGOUS PAIRS (ONE DOMINANT, ONE RECESSIVE) GENOTYPES

Back 23

HETEROZYGOUS (100%)

Front 24

If you cross 2 parent plants that are BOTH HETEROZYGOUS for a trait the offspring will show a ____ : ____ phenotypic ratio.
________ % of the offspring will show the DOMINANT trait and
________ % of the offspring will show the RECESSIVE trait.

Back 24

3:1
75
25

Front 25

USE DOMINANT OR RECESSIVE TO FILL IN THE BLANKS BELOW:
¼ of the offspring will have two __________________ alleles, ½ will be hybrids with one _______________ and one _______________ allele, and
¼ will have two _________________ alleles.

Back 25

recessive
dominant
recessive
dominant

Front 26

MAKE A CROSS WITH 2 HETEROZYGOUS FOUR O’CLOCK PLANTS.
Genotypes___________________________ Genotypic Ratio ______________________
Phenotypes __________________________
Phenotypic Ratios _____________________

Back 26

RR, rr, Rr
2:1:1
red,white,pink
2:1:1

Front 27

You are exploring the jungle and find a new species of plant. Some of the plants have red flowers and some have yellow flowers. You cross a red flowering plant with a yellow flowering plant and all the offspring have orange flowers. You might assume that the alleles for flower color in this plant show ____________________.

Back 27

incomplete dominance

Front 28

If the red and yellow alleles in the mystery jungle plant above showed CODOMINANCE instead, what might you expect a plant with one red allele and one yellow allele to look like?

Back 28

It would have red and yellow flowers together on one plant

Front 29

SEE A PATTERN FOR HOMOZYGOUS DIHYBRID CROSSES:

If you cross plants that are PURE DOMINANT for TWO TRAITS with plants that are PURE RECESSIVE for TWO TRAITS, ________ % of the offspring will look DOMINANT for BOTH traits and the ________________ traits will not show at all.

Back 29

100
recessive

Front 30

genes: factors that __________________________ -- the part of the DNA molecule containing the genetic code

Back 30

control organism traits

Front 31

alleles:

Back 31

different forms of a gene associated with a particular characteristic (ex. height : tallness/shortness)

Front 32

chromosomes: ____________________________________________________________

Back 32

hereditary units of an organism

Front 33

locus:

Back 33

particular point where a certain gene is found on a chromosome

Front 34

homologous chromosomes:

Back 34

pair of associated chromosomes -- each chromosome in the pair is called a homologue

Front 35

** Mendel developed some basic principles of heredity ______________________________________. His principles of dominance, segregation, and independent assortment were established through the ________________________ of large numbers of offspring produced by crossing pea plants.

Back 35

by breeding garden peas
mathematical analysis

Front 36

** As a result of analyzing specific mathematical ratios associated with certain characteristics in the offspring, Mendel proposed that characteristics were ______________ as the result of the transmission of ____________________________________.

Back 36

inherited
hereditary factors

Front 37

•Every organism requires a set of coded instructions for specifying its traits. For offspring to resemble their parents, their must be a reliable way to ____________________________________________ from one generation to the next.

Back 37

transfer hereditary information

Front 38

•Each gene carries a separate piece of information. An inherited trait of an individual can be determined by one or by many genes, and a single gene can influence _______________________________________________.

Back 38

more than one cell

Front 39

** Alleles are located in _________________________________________________ on homologous chromosomes.

Back 39

the same position as locus

Front 40

B. In asexually reproducing organisms, all the genes come from a ______________________. These genes are normally _________________ to the parent. (clone)

Back 40

single parent
identical

Front 41

C. Sexually reproducing organisms normally receive half their genetic information from the Mother's egg and half their genetic information from their Father's sperm. Sexually reproduced offspring ____________________________ ___________________________________ to their parents.

Back 41

resemble, but are not identical

Front 42

Mendel's hereditary factors, now called _____, exist at definite loci in a linear fashion on chromosomes. Two genes associated with a specific characteristic are known as __________ and are located on homologous chromosomes. The gene-chromosome theory provides the mechanism to account for the hereditary patterns which Mendel observed.

Back 42

genes
alleles

Front 43

1. __________ breeding: When the plants self-pollinate, all their offspring are of the same variety.

Back 43

True

Front 44

2. Hybridization: Mating, or _____________, of two varieties.

Back 44

crossing

Front 45

3. Monohybrid cross: A cross that tracks the inheritance of a _______________ character.

Back 45

single

Front 46

. homozygous (pure) --

Back 46

an individual with two of the same alleles on homologous chromosomes

Front 47

heterozygous: (hybrid) --

Back 47

an individual with contrasting alleles for the same trait on homologous chromosomes

Front 48

__________________ generation (P) -- the two original organisms being crossed

Back 48

Parental

Front 49

first ______________ generation (F1) -- the first generation of offspring from the parents

Back 49

filial

Front 50

second filial generation (F2) --

Back 50

generation of offspring arising from the first filial generation

Front 51

The __________________________________________states that for contrasting traits only the dominant trait can be seen. Mendel saw this unfold for all of the seven traits that he studied.

Back 51

law of dominance

Front 52

Law of Dominance (Mendel)
a pattern of heredity in which only _______________________ of an allelic pair is expressed

Back 52

one gene

Front 53

Law of Dominance (Mendel)
In the heterozygous condition, one allele of a gene may express itself and mask the presence of the other allele: EX.

Back 53

purple flowering X white flowering-->purple flowering peas

Front 54

Law of Dominance (Mendel)
________________________ trait: the trait or allele that is expressed

Back 54

dominant

Front 55

Law of Dominance (Mendel)
recessive trait: the trait or allele that is present but that is _________________________________

Back 55

masked by dominant trait

Front 56

Law of Dominance (Mendel)
progeny --

Back 56

offspring

Front 57

Law of Dominance (Mendel)
siblings --

Back 57

brothers or sisters

Front 58

Law of Dominance (Mendel)
Punnett square:

Back 58

used to represent genetic crosses

Front 59

Law of Dominance (Mendel)
genotype: the _________________________________ of an organism

Back 59

genetic makeup

Front 60

Law of Dominance (Mendel)
phenotype: the __________________________ of an organism

Back 60

physical characteristics

Front 61

Mendel wanted to know why the recessive trait disappeared in one generation and reappeared in the next generation. He came up with the _________________________________________.

Back 61

Principle of segregation and recombination

Front 62

Principle of Segregation and Recombination (Mendel)
Principle of segregation and recombination states that

Back 62

factors that occur in pairs are separated from each other during gamete formation and recombine at fertilization.

Front 63

Principle of Segregation and Recombination (Mendel)
When gametes are formed during meiosis there is ______________________________________ of homologous chromosomes.

Back 63

random segregation

Front 64

Principle of Segregation and Recombination (Mendel)
As a result of fertilization, alleles recombine. As a consequence, new allelic gene ______________________ are likely to be produced.

Back 64

combinations

Front 65

** Segregation and recombination is illustrated by the cross between

Back 65

two individuals heterozygous for a trait.

Front 66

Law of Independent Assortment (Mendel)
If the genes for two different traits are located on different chromosomes (nonhomologous chromosomes), they segregate randomly during meiosis and, therefore, may be ____________________ ____________________________________________________________

Back 66

inherited independently of each other

Front 67

Law of Independent Assortment (Mendel)
The cross of two organisms heterozygous for a trait is known as a ________________ cross.

Back 67

hybrid

Front 68

** Assuming large numbers of two organisms heterozygous cross, the phenotypic ratio of dominant offspring to recessive offspring is ________ and the genotypic ratio of homozygous dominant offspring to heterozygous dominant offspring to homozygous recessive offspring is ___________

Back 68

3:1
1:2:1

Front 69

The laws of probability- In tossing a coin there is a ______ percent chance that a head will turn up. However, it is quite possible for you to toss a coin 10 times and obtain 8 heads and 2 tails. The law of probability is based on ____________________________.

Back 69

50
sample size
number of trials

Front 70

Test Cross-
To find out whether an individual showing a dominant trait is homozygous( TT ) or heterozygous ( Tt ) the individual can be crossed with another showing the recessive trait. ( tt ) If there are any recessive traits produced in the offspring the unknown parent must be ____________________.

Back 70

heterozygous dominant

Front 71

Monohybrid Cross-

Back 71

A cross between individuals that involves one pair of contrasting traits

we use Punnett square diagrams to predict the results of various monohybrid crosses.

Front 72

Dihybrid Cross-

Back 72

a cross between individuals that involves two pairs of contrasting traits.
It is the simultaneous inheritance of two characteristics.
Predicting the results of a dihybrid cross is more complicated than predicting the results of a monohybrid cross.
All possible combinations of the four alleles from each parent must be considered.

Front 73

Incomplete Dominance - A case of contrasting alleles in which one allele is only ______________ dominant over the other --the dominant allele is only partially expressed when the recessive
allele is present. Sometimes called ___________________ inheritance

Back 73

partially
blending

Front 74

Codominance: a case of contrasting alleles in which _________________________ is dominant over the other (alleles have equal power)

Back 74

neither allele

Front 75

Multiple Alleles
In some traits more than two alleles can exist in a population of a species, but a single individual can only possess _____ alleles.

Back 75

two

Front 76

Multiple Alleles
Ex: Human blood type has _________________ types.

Back 76

four

Front 77

Multiple Alleles
However there are ____________alleles that control blood types they are________________________.

Back 77

three
A, B, AB, O

Front 78

A and B are both ____________ over O.

Back 78

dominant

Front 79

Neither A nor B is _________ Over each other (codominant)

Back 79

dominant

Front 80

Which red blood cells surface proteins are found on: Type A,

Back 80

A agglutinogens only

Front 81

Which red blood cells surface proteins are found on: Type B,

Back 81

B agglutinogens only

Front 82

Which red blood cells surface proteins are found on: Type AB,

Back 82

A and B agglutinogens only

Front 83

Which red blood cells surface proteins are found on: Type O?

Back 83

none

Front 84

Which plasma antibodies are produced by: Type A,

Back 84

B agglutinin

Front 85

Which plasma antibodies are produced by: Type B,

Back 85

A agglutinin

Front 86

Which plasma antibodies are produced by: Type AB,

Back 86

None

Front 87

Which plasma antibodies are produced by: Type O?

Back 87

A and B agglutinin

Front 88

Which blood types can be given and donated for type A

Back 88

Can give blood to A and AB
can receive blood from A and O

Front 89

Which blood types can be given and donated for type B

Back 89

Can give blood to B and AB
can receive blood from B and O

Front 90

Which blood types can be given and donated for type O

Back 90

Can give blood to AB, A, B, O (universal donor)
can receive blood from O

Front 91

Which blood types can be given and donated for type AB

Back 91

Can give blood to AB
can receive blood from AB, A, B, O (universal receiver)

Front 92

gene linkage: when genes for two different traits (non-allelic genes) are located on the ________________________ pair (homologous chromosomes) - Linked genes are __________________ inherited together

Back 92

same chromosome
usually

Front 93

The exception to gene linkage can be found when ____________________________ occurs. For example not all persons with red hair have freckles. This variation from the expected normal may be due to crossing over.

Back 93

crossing over

Front 94

crossing over:

Back 94

during synapsis in the first meiotic division, the chromatids in a homologous pair of chromosomes often twist around each other, break, exchange segments and rejoin

Front 95

Crossing over results in the _____________________________ of linked genes and increases the variability of offspring.

Back 95

rearrangement

Front 96

• Sex linkage is the _______________ expression of an __________ that is dependent on the sex of the individual and is directly tied to the ______________________________.

Back 96

phenotypic
allele
sex chromosome

Front 97

In sex linkage there is a homogametic sex and a heterogametic sex. In mammals the homogametic sex is female (XX) and the heterogametic sex is male (XY), thus the sex linked genes are carried on the _____________________.

Back 97

X Chromosome

Front 98

• Sex-linked traits are inherited through chains of carrier ______________. That is, a girl, her mother, and her mother's mother all are carriers, while some of their sons have the trait.

Back 98

mothers

Front 99

• X-linked genes are ______________ passed from father to son. The Y chromosome is the only sex chromosome that passes from father to son.

Back 99

never

Front 100

• Males are never _______________ – if they have a mutated gene on the X chromosome, it will be expressed

Back 100

carriers

Front 101

To "read" a set of human chromosomes, scientists first use three key features to identify their similarities and differences:
________. This is the easiest way to tell two different chromosomes apart.

Back 101

Size

Front 102

To "read" a set of human chromosomes, scientists first use three key features to identify their similarities and differences:
________________. The size and location of Giemsa bands on chromosomes make each chromosome pair unique.

Back 102

Banding pattern

Front 103

To "read" a set of human chromosomes, scientists first use three key features to identify their similarities and differences:
_____________________ Centromeres are regions in chromosomes that appear as a constriction. They have a special role in the separation of chromosomes into daughter cells during mitosis cell division (mitosis and meiosis).

Back 103

Centromere position.

Front 104

Using these key features, scientists match up the ___ pairs -- one set from the mother and one set from the father.

Back 104

23

Front 105

____________________ chromosomes- the centromere lies near the center of the chromosome.

Back 105

metacentric

Front 106

____________________ chromosomes- chromosomes have a centromere that is off-center, so that one chromosome arm is longer than the other. When chromosomes are aligned, they are oriented so that the short arm, designated "p" (for petite), is at the top, and the long arm, designated "q" (simply for what follows the letter "p"), is at the bottom.

Back 106

submetacentric

Front 107

____________________ chromosomes- the centromere resides very near one end.

Back 107

acrocentric

Front 108

Down Syndrome

Back 108

The effects of Down Syndrome vary greatly from person to person but can include mental retardation, eyes that slant upward, and heart defects.

People with Down Syndrome have 3 copies of chromosome 21. For this reason, Down Syndrome is also called "Trisomy 21".

Front 109

Turner Syndrome

Back 109

Symptoms include short stature and lack of ovarian development. Other features, such as webbed neck, arms that turn out slightly at the elbow, and a low hairline in the back of the head are sometimes seen.

Women and girls with Turner Syndrome have only one X chromosome. This is an example of monosomy.

Front 110

Klinefelter’s Syndrome

Back 110

People with this disorder develop as males with subtle characteristics that become apparent during puberty. They are often tall and usually do not develop secondary sex characteristics such as facial hair, or underarm and pubic hair.

Men and boys with Klinefelter Syndrome have a Y chromosome and 2 X chromosomes. This is an example of trisomy.

Front 111

Reciprocal Translocation: Philadelphia chromosome

Back 111

This translocation, which is found only in tumor cells, indicates that a patient has chronic myelogenous leukemia (CML). In CML, the cells that produce blood cells for the body (the hematopoietic cells) grow uncontrollably, leading to cancer.

This person has 46 chromosomes with a translocation of material between chromosome 9 and chromosome 22 (commonly known as the Philadelphia chromosome).

Front 112

Cri du chat Syndrome

Back 112

Cri du chat is a rare syndrome (1 in 50,000 live births) caused by a deletion on the short arm of chromosome 5. The name of this syndrome is French for "cry of the cat," referring to the distinctive cry of children with this disorder. The cry is caused by abnormal larynx development, which becomes normal within a few weeks of birth. Infants with cri du chat have low birth weight and may have respiratory problems. Some people with this disorder have a shortened lifespan, but most have a normal life expectancy.

Front 113

Williams Syndrome

Back 113

caused by a very small chromosomal deletion on the long arm of chromosome 7. The deleted region includes the elastin gene (see figures A and B below), which encodes a protein that gives blood vessels the stretchiness and strength required to withstand a lifetime of use. The elastin protein is made only during embryo development and childhood, when blood vessels are formed. Because they lack the elastin protein, people with Williams Syndrome have disorders of the circulatory system, also known as vascular disorders.

Front 114

karyotype

Back 114

a display of the chromosomes of a single cell. To obtain it, the cell is stained, then a picture is taken of it through a microscope just before cell division, when the chromosomes are easiest to see.

Front 115

Nondisjunction– failure of chromosome ____________ during meiosis (during ________).
Causes gamete to have too _____ or too ____ chromosomes

Back 115

to separate
anaphase
many or few

Front 116

Deletion – due to breakage
A piece of chromosome is ______

Back 116

lost

Front 117

Insertions and Deletions: Extra base pairs may be added (_____________________) or removed (___________________) from the DNA of a gene. The number can range from one to thousands. Collectively, these mutations are called _________. _________ involving one or two base pairs (or multiples thereof) can have devastating consequences to the gene because translation of the gene is "_______________". The mRNA is translated in new groups of three nucleotides and the protein specified by these new codons will be worthless. A number of inherited human disorders are caused by the insertion of many copies of the same triplet of nucleotides. Huntington's disease and the fragile X syndrome are examples of such ___________ __________diseases. Huntington’s Disease- An incurable form of insanity that does not show up until the age of 35-40. This disease is rather unique because it is dominant!!

Back 117

insertion

deletions

indels

indels

frameshifted

trinucleotide repeat

Front 118

Nondisjunction– failure of chromosome ____________ during meiosis (during ________).
Causes gamete to have too _____ or too ____ chromosomes

Back 118

to separate
anaphase
many or few

Front 119

Translocation– Involves two chromosomes that aren't ____________.
Part of one chromosome is ___________ to another chromosome.

Back 119

homologous

transferred

Front 120

The _________ determines if the offspring will be male or female?

Back 120

MALE

Front 121

Which sex is homogametic?

Back 121

female

Front 122

Which sex is Heterogametic?

Back 122

male

Front 123

EPIGENETICS

Back 123

changes in gene expression that are stable between cell divisions, and sometimes between generations, but do not involve changes in the underlying DNA sequence of the organism. Basically, it is a term used to describe the idea that environmental factors can cause an organism's genes to behave (or "express themselves") differently, even though the genes themselves don't change.

Front 124

Pedigree

Back 124

A Pedigree Chart is a chart which tells one all of the known phenotypes for an organism and its ancestors, most commonly humans, show dogs, and race horses.