Intro_2_RNA_and_Chromosomes_Flashcards

Question 1

What does RNA stand for?

Answer 1

Ribonucleic acid.

Question 2

Is RNA single-stranded or double-stranded?

Answer 2

Single-stranded.

Question 3

What are the basic building blocks of RNA?

Answer 3

Ribose sugar, phosphate group, and nitrogenous bases (A, G, C, U).

Question 4

Which base does RNA have instead of Thymine (T)?

Answer 4

Uracil (U).

Question 5

What is the backbone of RNA made of?

Answer 5

Alternating ribose sugars and phosphate groups.

Question 6

How is RNA different from DNA in terms of sugar?

Answer 6

RNA has ribose sugar; DNA has deoxyribose sugar.

Question 7

What is the function of messenger RNA (mRNA)?

Answer 7

Carries genetic code from DNA to ribosomes for protein synthesis.

Question 8

What is the role of ribosomal RNA (rRNA)?

Answer 8

Forms the core of ribosomes and facilitates protein synthesis.

Question 9

What does transfer RNA (tRNA) do?

Answer 9

Carries specific amino acids to ribosomes during protein synthesis.

Question 10

What are non-coding RNAs (ncRNAs)?

Answer 10

RNAs that don’t code for proteins but regulate gene expression.

Question 11

Give examples of ncRNAs.

Answer 11

microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and ribozymes.

Question 12

What percentage of transcriptional output in eukaryotes is ncRNAs?

Answer 12

About 97%.

Question 13

Name three functions of RNA.

Answer 13

Protein synthesis, gene regulation, and catalysis.

Question 14

What is a ribozyme?

Answer 14

An RNA molecule with catalytic activity.

Question 15

How does RNA size compare to DNA?

Answer 15

RNA molecules are much shorter than DNA.

Question 16

How long are most RNA molecules?

Answer 16

A few thousand nucleotides.

Question 17

How is RNA integrity assessed?

Answer 17

Using a denaturing agarose gel stained with ethidium bromide.

Question 18

What does a 2:1 intensity ratio of 28S to 18S rRNA bands indicate?

Answer 18

Intact RNA.

Question 19

What is chromatin?

Answer 19

A complex of DNA and proteins that make up chromosomes.

Question 20

Who discovered chromatin?

Answer 20

Walther Flemming.

Question 21

What is a nucleosome?

Answer 21

The basic unit of chromatin, with DNA wrapped around histone proteins.

Question 22

What are the levels of chromatin structure?

Answer 22

DNA double helix, nucleosome, 30 nm fiber, chromatin loops, chromosomes.

Question 23

What is euchromatin?

Answer 23

Less condensed chromatin that is gene-rich and transcriptionally active.

Question 24

What is heterochromatin?

Answer 24

Highly condensed chromatin that is gene-poor and transcriptionally inactive.

Question 25

Name the core histones in nucleosomes.

Answer 25

H2A, H2B, H3, and H4.

Question 26

What is the role of linker histone H1?

Answer 26

Binds linker DNA and helps form higher-order chromatin structures.

Question 27

What is the function of chromosomes?

Answer 27

To carry and protect DNA during cell division.

Question 28

What is a karyotype?

Answer 28

An organized visual representation of an individual's chromosomes.

Question 29

What is the function of the centromere?

Answer 29

Attaches chromosomes to spindle fibers during cell division.

Question 30

What are telomeres?

Answer 30

Repetitive DNA sequences at the ends of chromosomes that protect DNA from degradation.

Question 31

How many nucleotides are in the human genome?

Answer 31

About 3.2 billion.

Question 32

How many pairs of chromosomes are in the human genome?

Answer 32

23 pairs.

Question 33

What percentage of the human genome codes for proteins?

Answer 33

About 2%.

Question 34

What was the goal of the Human Genome Project?

Answer 34

To sequence the entire human genome.

Question 35

When was the Human Genome Project completed?

Answer 35

In 2003.

Question 36

What is genetic polymorphism?

Answer 36

Variations in DNA sequences among individuals or populations.

Question 37

What is a single nucleotide polymorphism (SNP)?

Answer 37

A DNA sequence variation involving a single nucleotide difference.

Question 38

What are tandem repeats?

Answer 38

Repetitive DNA sequences where the number of repeats varies between individuals.

Question 39

What is DNA fingerprinting used for?

Answer 39

Forensic investigations and paternity testing.

Question 40

How do RNA and DNA differ in structure?

Answer 40

RNA is single-stranded; DNA is double-stranded.

Question 41

What sugar is found in RNA but not in DNA?

Answer 41

Ribose (DNA has deoxyribose).

Question 42

What base does RNA have that DNA does not?

Answer 42

Uracil (DNA has Thymine).

Question 43

What is a nucleotide?

Answer 43

The building block of DNA and RNA, consisting of a sugar, phosphate group, and nitrogenous base.

Question 44

What is a nucleoside?

Answer 44

A nucleotide without the phosphate group.

Question 45

What are purines?

Answer 45

Double-ring nitrogenous bases (A and G).

Question 46

What are pyrimidines?

Answer 46

Single-ring nitrogenous bases (C, T, and U).

Question 47

What bonds link nucleotides in RNA and DNA?

Answer 47

Phosphodiester bonds.

Question 48

What does the RNA backbone consist of?

Answer 48

Ribose sugars and phosphate groups.

Question 49

What is the function of mRNA?

Answer 49

Carries the genetic code from DNA to ribosomes for translation.

Question 50

What is the role of histones in chromatin?

Answer 50

Organizing and compacting DNA into nucleosomes.