Heredity & Societies Transmission Genetics (Lectures 4-6)

Question 0

Why did Mendel use peas?

Answer 0

Identifiable traits
Easy to grow
Take little space 
Inexpensive
Short growth period
Self fertilizing
Artificially fertilized

Question 1

Who is Johan Gregor Mendel

Answer 1

• monk

- expired mended peas to understand fundamental principles of genetics

Question 2

What was mendle’s experimental design?

Answer 2

Large sample size over 10 yr period
7 different traits
Repeated experiments 
Analyzed data with probability and statistics
Lack of preconceived notion

Question 3

Allele

Answer 3

Alternate form or variation of gene

Question 4

2 types of alleles

Answer 4

Homozygous and heterozygous

Question 5

Homozygous

Answer 5

Two identical alleles for a gene

Question 6

Heterozygous

Answer 6

Two different alleles for a gene

Question 7

Phenotype

Answer 7

Physical trait of an organism; obserable

Question 8

Genotype

Answer 8

Genetic constitution of an organism

Question 9

Dominant

Answer 9

The allele that the organism’s appearance

Question 10

Recessive

Answer 10

alleles that has no noticeable effect on the appearance

Question 11

Mendel’s first law

Answer 11

Principle of segregation

• members of a gene pair separate during the formation of gametes
• genes must separate during gametes formation so that each game contributes one gene to the zygote

Question 12

Mendel’s Second Law

Answer 12

Principle of Independent Assortment: alleles of one pair of genes segregate into gametes independent of the alleles from another gene pair. Genes are packaged into gametes randomly

Question 13

Mendelian inheritance in humans pigmentation gene and albinism

Answer 13

75% normals

25% albino

Question 14

What is albinism

Answer 14

Pigmentation dominant and lack of pigment recessive 3:1 ratio

Question 15

Where are autosomal traits located?

Answer 15

Human autosomal traits are located on the non sex chromosomes (1-22)

Question 16

What are autosomal traits

Answer 16

They may be inherited as auto sales recessive or autosomal dominant. The non sex chromosomes

Question 17

Pedigree

Answer 17

Depicts family relationships and patterns of inheritance for particular traits

Question 18

Autosomal Recessive

Answer 18

• Unaffected parents have affected children
• All children of affected parents are affected
• Both parents Aa, risk affected child -25%
• Equal affected male and female
• consanguinity

Question 19

Consanguinity

Answer 19

Kissing cousins

Question 20

Autosomal recessive traits

Answer 20

• cystic fibrosis
• Tay sacks disease
• Sickle cell anemia
• albinism
• attached ear lobes

Question 21

Autosomal Dominant

Answer 21

• requires one copy -mutant allele (Aa)- rarely (AA)
• aa: unaffected individuals
• affected individual- at least one affected parent
• Aa x aa: each child- 50%chance- affected
• Equal numbers- males and females two affected individuals -unaffected children

Question 22

X Linked Recessive

Answer 22

• males: homozygous for genes on the X (doesn’t have an allied counter part)
• affected makes get faulty allele from mom- transmit to daughter but not son
• daughters of affected makes are heterozygous, thus unaffected
• for recessive traits, XX and XY affected
• more males affected

Question 23

Autosomal dominant traits

Answer 23

• Marfan syndrome
• Ectrodactyly
• Neurofibromatosis
• Huntington disease
• Widow’s peak, freckles

Question 24

X linked recessive traits

Answer 24

- hemophilia - color blindness - muscular dystrophy

Question 25

Hemophilia

Answer 25

Blood does not clot, bleed to death | Royal disease

Question 26

Color blindness

Answer 26

More male 1/12 | Women 1/200

Question 27

X linked dominant

Answer 27

Affected males- all affected daughter but no affected sons | Heterozygous females- unaffected and affected offspring;- equally affected

Question 28

X linked dominant traits

Answer 28

Hypophosphatemia | And some types of hereditary hearing loss

Question 29

Y linked

Answer 29

Passes only father to sons Women never affected Doesn't skip generations Y linked traits -rare-Y has fewer genes

Question 30

Mitochondrial inheritance- non Mendelian inheritance

Answer 30

Mitochondria- have their own dna - transmitted from mother to all of her offspring - males and females equally affected

Question 31

Who can pass down mitochondria

Answer 31

Mom

Question 32

Polygenic traits/ disorders

Answer 32

Are determined by two or more genes -eye color

Question 33

Multi factorial traits

Answer 33

``` Controlled by two or more genes and show significant interaction with the environment Height Skin Color Diabetes Obesity Cardiovascular Cancer ```

Question 34

Twin studies

Answer 34

- Used often in studies to determine the influence of heredity and environment on the phenotype - identical genes- if not identical in phenotype, may be deduced that environmental influences exists - debate over nature vs nurture

Question 35

What can the environment influence

Answer 35

The genotype to produce the phenotype

Question 36

Risk factors for cardiovascular disease

Answer 36

``` Heredity Male Hypertension ldl (low density lipoproteins) or Hdl (high density lipoproteins) Smoking Obesity Lack of exercise Stress ```

Question 37

Survey of multi factorial traits complex traits

Answer 37

``` Cardiovascular disease Diabetes Obesity Behavior Intelligence ```

Question 39

Monozygotic twins

Answer 39

two offspring born of the same pregnancy and developed from a single fertilized ovum that splits into equal halves during an early cleavage phase in embryonic development, giving rise to separate fetuses

Question 39

Dizygotic twins

Answer 39

two offspring born of the same pregnancy and developed from two ova that were released from the ovary simultaneously and fertilized at the same time.

Question 40

Neural tube defects

Answer 40

A group of disorders that result from defects in the formation or development of the neural tube

Question 41

Cystic fibrosis

Answer 41

damage to the lungs and digestive system.

Question 42

Sickle cell anemia

Answer 42

loose oxygen. outside in the sun. common in African Americans,

Question 43

hemizygous

Answer 43

Having only a single copy of a gene instead of the customary two copies.

Question 44

muscular dystrophy

Answer 44

progressive weakness and loss of muscle mass. In muscular dystrophy, abnormal genes (mutations) interfere with the production of proteins needed to form healthy muscle.

Question 45

Huntington disease

Answer 45

nerve cells in the brain. Huntington's disease has a broad impact on a person's functional abilities and usually results in movement, thinking (cognitive) and psychiatric disorders.30s or 40s

Question 46

locus or loci

Answer 46

location of the gene/allele

Question 47

genes

Answer 47

Carries of genetic information in the form of DNA

Question 48

Marfan syndrome

Answer 48

weakness in connective tissue

Question 49

Ectrodactyly

Answer 49

lobster claw syndrome