Chapter 10.1

Question 1

Alleles

Answer 1

one of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome.

They are alternative forms, each arising from a different mutation

Question 2

DNA

Answer 2

a molecule that encodes all the information needed to sustain life

Question 3

How much ( approx ) genes does DNA have

Answer 3

25,000 genes

Question 4

GENE

Answer 4

A portion of DNA whose sequence of nucleotides (A< and T) encodes a protein

Question 5

How is DNA in eukaryotes packaged

Answer 5

They are divided among multiple chromosomes

Question 6

CHROMOSOMES

Answer 6

They are long strands of DNA ( in its condensed form) with associated proteins

Question 7

DIPLOID CELL

Answer 7

contain two sets of chromosomes, with one set inherited from each parent

Question 8

The human genome consists of how many chromosomes

Answer 8

23 pairs

Question 9

AUTOSOMES

Answer 9

chromosomes that are the same for both sexes ( somatic cells)

Question 10

SEX CHROMOSOMES

Answer 10

The single pair of chromosomes that determines whether a person is male or female

Question 11

A female is designated with what sex chromosome

Answer 11

a person with two (2) X chromosomes :XX

Question 12

A male is designated with what sex chromosome

Answer 12

has (1) X and (1) Y : XY

Question 13

An analogy to the human genome stored on DNA is that of instructions stored in a book:

Answer 13

.The book (genome) would contain 23 chapters (chromosomes);
.Each chapter contains 48 to 250 million letters (A,C,G,T) without spaces;
.Hence, the book contains over 3.2 billion letters total;
.The book fits into a cell nucleus the size of a pinpoint;
.At least one copy of the book (all 23 chapters) is contained in most cells of our body. The only exception in humans is found in mature red blood cells which become enucleated during development and therefore lack a genome.

Question 14

HOMOLOGOUS CHROMOSOME

Answer 14

are similar but not identical. Each carries the same genes in the same order, but the alleles for each trait may not be the same. In garden peas, for example, the gene for pod colour on the maternal chromosome might be the yellow allele; the gene on the homologous paternal chromosome might be the green allele.

They look alike and have the same sequence of genes in the same position, but may or may not carry the same alleles (translation/ version of the gene)

Question 15

How many alleles of each gene does each person inherit

Answer 15

2 allele for each gene, since homolog comes from a different parent

Question 16

An analogy for the 2 alleles for each gene

Answer 16

are comparable to two brownie recipes in a cell may be exactly the the same , slightly different or very different from each other.
with the exception of identical twins , everyone inherits a unique combination of alleles for all the genes in the human genome.

Question 17

Meiosis

Answer 17

a specialized form of cell division that occurs in diploid cells and give rise to haploid cells

Question 18

HAPLOIDS CELLS

Answer 18

each containing 1 set of of chromosomes ( n=23)

Question 19

DIPLOID CELLS

Answer 19

each contain 2 sets of chromosomes in each cell. 2n =46

Question 20

What pairs of chromosomes are not homologous

Answer 20

The sex chromosomes X and Y

Question 21

A gene’s LOCUS

Answer 21

Is its physical place on the chromosome

Question 22

GAMETES

Answer 22

Haploid cells in humans/ sex cells
1. egg cells
2. sperm cells
They are the cells that convey chromosomes from one generation to the next

Question 23

FERTILIZATION

Answer 23

unites the gametes from 2 parents

Question 24

Describe the relationships among chromosomes, DNA, genes, and alleles.

Answer 24

Chromosomes contain tightly packed DNA and associated proteins. DNA are the strands of genetic material that contains genes, sequences of nucleotides that code for amino acids. Those genes come in varieties called alleles.

Question 25

How do meiosis, fertilization, diploid cells, and haploid cells interact in a sexual life cycle?

Answer 25

Meiosis in the adult organism creates the haploid gamete cells that combine during fertilization to form the diploid zygote cell. That cell undergoes mitosis to make the cells that are necessary for growth into the adult form.