Heredity Lab

Question 1

Heredity

Answer 1

The passing on of physical characteristics from parents to their off spring

Question 2

How are traits passed on?

Answer 2

Through chromosomes in sperm and egg cells

Question 3

Chromosomes

Answer 3

DNA strands composed of gene units

Question 4

Genes

Answer 4

Chromosome sections

• contains codes for specific physical and chemical characteristics

Question 5

Define traits

Answer 5

Specific physical or chemical characteristics of an individual
•passed on with chromosomes in egg and Sperm cells

Question 6

Type of traits

Answer 6

Dominant

Recessive

Question 7

Dominant traits

Answer 7

Always seen expressed in offspring 
•free earlobe
•hair in hands
•bent fingers
•tongue rolling

Question 8

Recessive traits

Answer 8

Not always seen
•hidden traits
•not expressed

Question 9

Inheritance traits

Answer 9

Many traits are inherited on pairs of genes located on separate homologous (look alike) chromosomes

Question 10

Traits inherited on pairs of genes located on separate homologous chromosomes are called

Answer 10

Alleles genes

Question 11

Phenotype

Answer 11

Physical appearance of an individual

Question 12

Geneotype

Answer 12

Inherited gene combination for a specific trait
Two types:
•homozygous
•heterozygous

Question 13

Homozygous

Answer 13

Alleles of pair have same information

DD dd

Question 14

Heterozygous

Answer 14

Allele genes have different information

Dd

Question 15

What is unique about the phenotype for the human trait, red hair?

Answer 15

Develops from a dominant allele on a different gene pair

•inhibits the expression of the first pair

Question 16

Somatic cells

Answer 16

Make up the body structure
•most of cells that make up body structure are somatic
•contain 46 chromosomes 23 pairs

Question 17

Name two reproductive cells

Answer 17

Sperm and egg

Question 18

How many chromosomes do the reproductive cells contain?

Answer 18

Contain 23 chromosomes, one of each original pairs

Question 19

Haploid

Answer 19

Another way to write chromosome numbers

•N=23 (only half)

Question 20

Diploid

Answer 20

•2N=46

Question 21

Meiotic division

Answer 21

• two cell divisions occur here

* go through 4 phases

Question 22

Four phases of meiosis

Answer 22

Prophase
Metaphase
Anaphase
Telophase

Question 23

What is the final result if meiosis?

Answer 23

4 daughter cells containing 23 chromosomes each
•male: 4 sperm
•female: 3 polar bodies
1 egg

Question 24

Spermatogenesis

Answer 24

Process of sperm cell formation in the seminiferous tubules of the testes

Question 25

Meiosis I

Answer 25

Primary spermatocytes divide to form two secondary spermatocytes •cell duplicates chromosomes 46 to 92 •chromosome pairs separate In reduction division •makes 46 and 46

Question 26

Meiosis II

Answer 26

* secondary spermatocytes divide into spermatids | * chromatids separate into four 23 chromosome spermatids

Question 27

Oogenesis

Answer 27

Process of egg cells formed in the ovary and released at ovulation

Question 28

Stages if oogenesis

Answer 28

* oogonia cells are present from birth, only a few will develop into primary oocytes * meiosis I and II

Question 29

Meiosis I female

Answer 29

* first cell division prior to ovulation * a secondary oocyte and polar body are produced * chromosome pairs separate in this division * 46 to 2x23 chromosomes

Question 30

Meiosis II female

Answer 30

* occurs after ovulation * single egg cell results, secondary oocyte * equals 23 chromosomes and polar body with Xtra chromosomes

Question 31

Karyotyping

Answer 31

* method of observing human chromosomes * a picture of chromosomes is produced * homologous pairs are arranged together

Question 32

Chromosome types

Answer 32

* Autosomes | * sex chromosomes

Question 33

Autosomes

Answer 33

Chromosome pair 1-22 | •have genetic codes for most body parts

Question 34

Sex chromosomes

Answer 34

23rd pair •contain codes for sex of an individual Female: XX Male: Xy

Question 35

Use if karyotypes

Answer 35

•determine sex of an individual •determine chromosome number •predicts phenotypes from normal or abnormal patterns -may see missing chromosomes -additions or deletions may be present on same chromosomes

Question 36

Non-disjunction

Answer 36

Unequal separation of chromosomes during either meiosis I or meiosis II

Question 37

Autosomal non-disjunction

Answer 37

Unequal separation of Autosomes chromosomes (1-22) during meiosis results in too few or two many chromosomes in sperm or egg cell

Question 38

Sex chromosome non-disjunction

Answer 38

An unequal separation of the X or Y chromosomes occurs during meiosis I or II

Question 39

Turners syndrome

Answer 39

``` 45 total (only one X chromosome) •phenotype: female ```

Question 40

Fertilization

Answer 40

* union if sperm (23) and egg (23) * the resulting fertilized cell called zygote * has 46 chromosomes total

Question 41

Identical twins

Answer 41

* cells become separated early in cleavage process, each cell forming new individual * each has same genetic make up * look alike * monozygotic formation * 1 egg

Question 42

Monozygotic formation

Answer 42

Coming from a single zygote

Question 43

Fraternal twins

Answer 43

``` More than one egg, fertilized by separate sperm cell •dizygotic •different genetic make up •same or opposite sex •multiple eggs ```

Question 44

Dizygotic

Answer 44

2 different zygotes are formed