Chapter 24: Genes and Chromosomes

Question 1

Gregor Mendel

Answer 1

“father of genetics”

Question 2

Mendel studied the garden pea for two main reasons:

Answer 2

1) A large variety were available.

2) Can self-pollinate (“self”) or cross the peas.

Question 3

How are plants crossed?

Answer 3

Taking pollen from one plant and fertilizing another

Question 4

Cross with plants differing in one character.

Answer 4

Monohybrid Cross

Question 5

TRUE/FALSE:

Mendel started his investigations by first obtaining “pure lines” (he grew these for two years).

Answer 5

True

Question 6

Phenotype

Answer 6

Physical appearance

Question 7

First Filial Generation

Answer 7

F1 or filial 1 hybrid offspring(s) of the first filial generation of distinctly different parental types.

Question 8

Second Filial Generation

Answer 8

F2 or filial 2 hybrid offspring(s) of a self or cross between individuals from the first filial generation

Question 9

Dominance and Recessive are defined by which phenotype

Answer 9

F1

Question 10

What is Mendel’s 1st law?

Answer 10

Each particle separates (segregates) equally into the gametes (egg and sperm).

Question 11

ex:

Each adult pea has 2 particles for each character studied.

Answer 11

Alleles of a gene

Question 12

Hereditary determinants of particulate nature.

Answer 12

Genes

Question 13

Allele

Answer 13

Each gamete carries only 1 particle.

Question 14

Gametes can combine without regard to which particle ____ is carried.

Answer 14

Allele

Question 15

“Green Seeds, Yellow Seeds” are examples of?

Answer 15

Phentotypes

Question 16

Allele symbols “y”, “Y” are examples of?

Answer 16

Genotypes

Question 17

one of the different forms of a gene that can exist.

Answer 17

Allele

Question 18

TRUE/FALSE:

alleles differ in DNA base sequences.

Answer 18

True

Question 19

DNA –> RNA

Answer 19

Transcription

Question 20

RNA –> Protein

Answer 20

Translation

Question 21

behavior of Mendel’s “particles”

(alleles of a gene) parallels the behavior of chromosomes during

Answer 21

meiosis (gamete production)

Question 22

Heterogametic sex

Answer 22

XY

Question 23

Homogametic sex

Answer 23

XX

Question 24

Non-sex chromosomes are called

Answer 24

autosomes

Question 25

Humans have how any chromosomes?

Answer 25

46 chromosomes (23 pairs) per cell (44 autosomes + 2 sex chromosomes)

Question 26

Do Sex linked genes only contribute to sexual function?

Answer 26

No. They could be involved in eye color, | hair loss, etc..

Question 27

Genes on autosomes show the kind of ____ ____ studied by Mendel.

Answer 27

inheritance patterns

Question 28

When inheritance patterns are different in males and | females, they are said to show ____ ____

Answer 28

sex linkage

Question 29

Discovery of double-helical structure of DNA in 1953 laid...thinking of biomolecules as carriers of information. Proteins play roles of catalysts but their role in information transfer was unclear. Francis Crick's “Once information has got into a protein it can’t get out again”. The Central Dogma was proposed by Francis Crick at the time when there was little evidence to support it

Answer 29

Central Dogma of Molecular Biolology

Question 30

Information from parental DNA is copied to daughter | DNA with high fidelity

Answer 30

DNA replication

Question 31

RNA is synthesized using DNA as a template

Answer 31

Transcription

Question 32

Viruses are able to make RNA and DNA using RNA | as a template

Answer 32

Reverse Transcription

Question 33

1. DNA replication 2. Transcription 3. Reverse transcription 4. Proteins are synthesized based on the information stored in ribonucleotide triplets in RNA

Answer 33

Information flow of according to Central Dogma

Question 34

TRUE/FALSE: Protein sequence determines its biological function

Answer 34

True

Question 35

One strand of double stranded DNA | acts as molecular template for RNA synthesis

Answer 35

Transcription

Question 36

The triplets of nucleotides in mRNA are matched with corresponding amino acids via triplets of tRNA

Answer 36

Translation

Question 37

TRUE/FALSE: Protein sequence determines its biological function

Answer 37

True

Question 38

DNA in the virion or cell is organized into ____ _____ , typically via coiling and association with proteins

Answer 38

compact forms

Question 39

Chromosome consists of covalently connected | ____ ______and associated proteins

Answer 39

, one, DNA molecule

Question 40

Viral genomic DNA may be associated with

Answer 40

capsid proteins

Question 41

Prokaryotic DNA is associated with proteins in the

Answer 41

nucleoid

Question 42

Chromatin

Answer 42

where Eukaryotic DNA is organized with proteins into a | complex

Question 43

smaller circular DNA molecules

Answer 43

Plasmids

Question 44

Bacterial Genome Usually Consists of ____ Circular Chromosome

Answer 44

One

Question 45

Eukaryotic DNA is Organized into ____ Chromosomes

Answer 45

Many

Question 46

TRUE/FALSE: Mitochondria and Chloroplasts have their own DNA

Answer 46

True

Question 47

TRUE/FALSE: Total length of DNA, nor the number of chromosomes correlates strongly with the perceived complexity of the organisms

Answer 47

True

Question 48

Introns

Answer 48

do not encode the polypeptide sequence are removed in nearly all eukaryotic genes (25% of sequenced bacterial genomes show presence of introns)

Question 49

Exons

Answer 49

sequences are spliced together after mRNA synthesis

Question 50

Introns in bacterial chromosome

Answer 50

interrupt mainly tRNA sequences

Question 51

Introns in phage genomes within bacteria

Answer 51

interrupt protein-coding sequences

Question 52

encode for catalytic RNA molecules that | have ability to insert and reverse transcribe themselves into the genomic DNA

Answer 52

bacterial introns

Question 53

Can move around within the genome of a single cell The ends contain terminal repeats that hybridize with the complementary regions of the target DNA during insertion

Answer 53

Transposons

Question 54

How much of the total genome encodes for proteins?

Answer 54

1.5%

Question 55

Biological significance of non-coding | sequences include:

Answer 55

-Participate in the regulation of gene expression (promoters, termination signals, etc) – Encodes small regulatory RNA with poorly understood functions – Junk (pieces of unwanted genes, remnants of viral infections)

Question 56

cap the ends of linear chromosomes and | are needed for successful cell division

Answer 56

Telomeres

Question 57

Centromere

Answer 57

Functions in cell division; two sister chromatids are held together during mitosis

Question 58

As cellular DNA ages, telomeres are

Answer 58

shortened after each round of replication

Question 59

DNA must be organized to allow:

Answer 59

Packing of large DNA molecules within the cells Access of proteins to read the information in DNA sequence

Question 60

TRUE/FALSE: Normal plasmid DNA in bacteria is usually supercoiled

Answer 60

True

Question 61

What is one of the several levels of DNA organization?

Answer 61

supercoiling of the double-stranded | DNA helix

Question 62

Nucleosomes consist of DNA wrapped around | positively charged ______ ______

Answer 62

histone proteins

Question 63

_____ ____ is thought to stabilize the nucleosome's 30 nm fiber

Answer 63

Histone H1

Question 64

Higher Levels of Chromatin Structure

Answer 64

- contain topoisomerase II - some poorly characterized proteins - involves coils upon coils...

Question 65

TRUE/FALSE: protein-coding regions represent only a small fraction of the total DNA

Answer 65

True

Question 66

Bacterial DNA is usually ______ for efficient packing

Answer 66

supercoiled

Question 67

Telomeres and centromeres are present in

Answer 67

eukaryotes

Question 68

_____ _____ wound around positively charged histones

Answer 68

Eukaryotic DNA