Heredity

Question 1

Distinct segments of chromosomal DNA that are transmitted from parent to offspring and cary the genetic code

Answer 1

Genes

Question 2

Genes determine the

Answer 2

Hereditary traits

Question 3

Each gene may have multiple variants or

Answer 3

Alleles

Question 4

Chromosomes and their genes exist in

Answer 4

Pairs

Question 5

How many chromosomes in humans

Answer 5

46 chromosomes (23 pairs)

Question 6

Chromosomes that are not involved in sex determination are

Answer 6

Autosomes (22 pairs of these or 44 chromosomes)

Question 7

The paired autosomes carry genes for the

Answer 7

Same traits at the same sites as each other

Question 8

Each variant of autosomes is known as an

Answer 8

Allele

Question 9

Homozygous means

Answer 9

Botha genes are same

Question 10

Heterozygous means

Answer 10

The two genes differ

Question 11

Dominant genes are always

Answer 11

Expressed, if present

Question 12

Dominant genes need to inherit from only

Answer 12

One parent

Question 13

Recessive genes are only expressed if

Answer 13

Homozygous
(Need to inherit from both parents)

Question 14

Recessive traits MUST HAVE

Answer 14

Homozygous alleles

Question 15

Phenotype refers to

Answer 15

An observable or testable characteristic
(Ex. Eye colour, blood type)

Question 16

Genotype refers to

Answer 16

Ones genetic makeup

Question 17

Homozygous recessive example

Answer 17

bb
*phenotype is recessive

Question 18

Homozygous dominant example

Answer 18

BB
*phenotype is dominant

Question 19

Heterozygous example

Answer 19

Bb

Question 20

A punnet square is used to determine

Answer 20

The probability of inheriting genetic traits

Question 21

Capital letters represent

Answer 21

Dominant allele

Question 22

Lower case letter represents

Answer 22

Recessive allele

Question 23

Reproductive cells are produced by

Answer 23

Meiosis

Question 24

Meiosis is the process that divides the # of chromosomes in half. How many meiotic divisions

Answer 24

2

Question 25

The first meiotic division distributes the chromosome pair into

Answer 25

Separate cells

Question 26

The second meiotic division separates the strands of the duplicated chromosome and

Answer 26

Distributes to an individual gamete

Question 27

Sex chromosomes determine the

Answer 27

Sex of the offspring

Question 28

Are sex chromosomes matched?

Answer 28

No

Question 29

Female chromosome is larger and is depicted as?

Answer 29

X

Question 30

Male chromosome is small and mainly determines sex. Depicted by

Answer 30

Y

Question 31

Non sexual traits carried on the sex chromosome are sec linked traits and most are

Answer 31

X-linked traits

Question 32

By meiosis each sperm received

Answer 32

An X or a Y

Question 33

By meiosis each egg receives only

Answer 33

An X

Question 34

Normal females have

Answer 34

2 X chromosomes - XX as pair 23

Question 35

Normal males have

Answer 35

X and Y chromosome -XY as pair 23

Question 36

Traits carried on a sex chromosome are termed

Answer 36

Sex linked traits

Question 37

Most sex linked traits are carried on the

Answer 37

X chromosome and are best described as X-linked

Question 38

Most sex linked traits are

Answer 38

Recessive

Question 39

Hereditary traits can be

Answer 39

Observable (skin, eyes, hair color, facial features) Or less clearly defined (weight, body build, life span, disease susceptibility)

Question 40

Human traits and genetic diseases can be determined by

Answer 40

A single pair of genes (less common) Or multifactorial inheritance

Question 41

Multifactorial inheritance refers to

Answer 41

Result of 2 or more gene pairs acting together -can include environmental factors -produces a wide range of variation in traits such as weight, height, skin colouration

Question 42

Gene expression is influenced by

Answer 42

Gender Other genes (codominance, incomplete dominance) The environment

Question 43

Genetic mutation is a change in the

Answer 43

Genetic code within a gene or chromosome

Question 44

Genetic mutation may be

Answer 44

Hereditary

Question 45

Genetic mutation is often caused by

Answer 45

Mutagens

Question 46

What are some agents that cause mutations

Answer 46

Chemicals, radiation, drugs or viruses

Question 47

Genetic mutation: what agents cause damage during embryonic development

Answer 47

Teratogenic agents (teratogens)

Question 48

Chromosomal breakage is aka

Answer 48

Non disjunction

Question 49

Most common non hereditary genetic disorder

Answer 49

Down syndrome or trisomy 21 *3 chromosomes at the 21 position so 47 in total

Question 50

What is turner syndrome

Answer 50

Aka monosomy X Only one sex cell is present, the X chromosome -commonly self aborts (1%survive and are born)

Question 51

Chromosomal disorder where 1 in 600 males are affected. Caused by the presence of 2 or more X chromosomes in a male. Affects males physical and cognitive development

Answer 51

Kkinefelter Syndrome

Question 52

Congenital disease means

Answer 52

Present at birth (May or may not be hereditary)

Question 53

Hereditary diseases means

Answer 53

Genetically transmitted (May not be evident at birth and manifests later in life)

Question 54

Huntington disease is hereditary and is characterized by? What chromosome does it affect?

Answer 54

Characterized by progressive degeneration of the brain Affects chromosome 4.

Question 55

Causes of congenital disorders?

Answer 55

Often idiopathic (unknown cause) Infections/toxins transmitted from mother Teratogen Ionizing radiation Alcohol intake Cigarette smoking Poor nutrition

Question 56

Karyotype refers to

Answer 56

The number and visual appearance of chromosomes of a cell. -an individuals complete set of chromosomes

Question 57

What is amniocentesis

Answer 57

Involves collection of fetal cells floating in amniotic fluid used to detect abnormalities