Biology Chapter 12 TEST Flashcards
41 Questions
100 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What stores information in a cell?

DNA

In what way is DNA like a book?

DNA has stored information that can be copied and passed on

Which of the following is a nucleotide found in DNA?

deoxyribose + phosphate group + cytosine

Because of base pairing in DNA, the percentage of what is about equal to the percentage of pyrimidine?

<p>purines</p> Signup and view all the answers

How did Rosalind Franklin contribute to the understanding of DNA?

<p>producing images of DNA molecules using X-rays</p> Signup and view all the answers

Which scientist(s) figured out that the shape of a DNA molecule was a double helix?

<p>Watson and Crick</p> Signup and view all the answers

What is the chronological order of the important discoveries in the structure of DNA?

<p>Chargaff's ratios of nucleotides &gt; Franklin makes an X-ray diffraction photo of DNA &gt; Watson and Crick identify the double helix</p> Signup and view all the answers

Which base forms a pair with thymine?

<p>adenine</p> Signup and view all the answers

What did Rosalind Franklin contribute to the effort to identify the structure of DNA?

<p>X-ray diffraction photos of the DNA molecule</p> Signup and view all the answers

DNA replication results in how many DNA molecules?

<p>two DNA molecules, each with one new strand and one original strand</p> Signup and view all the answers

During DNA replication, a DNA strand that has the bases CTAGGT produces a strand with what bases?

<p>GATCCA</p> Signup and view all the answers

In eukaryotes, DNA is located where?

<p>in the nucleus</p> Signup and view all the answers

In both prokaryotes and eukaryotes, DNA replication happens when?

<p>before cell division</p> Signup and view all the answers

RNA contains what type of sugar?

<p>ribose</p> Signup and view all the answers

These are found in both DNA and RNA.

<p>phosphate groups, guanine, and cytosine</p> Signup and view all the answers

RNA is usually single stranded.

<p>True</p> Signup and view all the answers

This type of RNA brings the information in the genetic code from the nucleus to other parts of the cell.

<p>mRNA</p> Signup and view all the answers

This is true of eukaryotic DNA.

<p>Introns are sequences of DNA</p> Signup and view all the answers

These molecules are involved in protein synthesis.

<p>mRNA, rRNA, and tRNA</p> Signup and view all the answers

From which molecules are mRNA molecules transcribed?

<p>DNA</p> Signup and view all the answers

What is produced during transcription?

<p>RNA molecules</p> Signup and view all the answers

During eukaryotic transcription, an RNA molecule is formed that is what?

<p>complementary to part of one strand of DNA</p> Signup and view all the answers

How many nucleotides are needed to specify three amino acids?

<p>9</p> Signup and view all the answers

There are 64 codons and 20 amino acids. Which is true?

<p>True</p> Signup and view all the answers

What happens during translation?

<p>the cell uses a messenger RNA code to make proteins</p> Signup and view all the answers

During translation, the type of amino acid that is added to the growing polypeptide depends on what?

<p>the codon on the mRNA and the anticodon on the tRNA</p> Signup and view all the answers

A protein is being assembled when what occurs?

<p>RNA is being translated</p> Signup and view all the answers

Genes contain instructions for assembling what?

<p>proteins</p> Signup and view all the answers

What is the correct sequence of the transfer of information in most organisms?

<p>DNA to RNA to protein</p> Signup and view all the answers

What is a mutation that involves one or a few nucleotides called?

<p>a point mutation</p> Signup and view all the answers

Give an example of a chromosomal mutation.

<p>inversion</p> Signup and view all the answers

When a chromosome undergoes a deletion mutation, information is what?

<p>lost</p> Signup and view all the answers

Most mutations have no effect on an organism.

<p>True</p> Signup and view all the answers

DNA is a nucleic acid made up of nucleosomes joined into long strands or chains by covalent bonds.

<p>False</p> Signup and view all the answers

The nucleotides within a DNA strand may have different nitrogenous bases but all have identical sugar molecules.

<p>True</p> Signup and view all the answers

Chargaff contributed to the understanding of DNA by figuring out that the percentages of adenine and thymine were almost equal in any sample of DNA.

<p>True</p> Signup and view all the answers

Watson and Crick used the image of DNA taken by Franklin in their work to figure out the structure of DNA.

<p>True</p> Signup and view all the answers

What are the three types of RNA?

<p>messenger RNA, transfer RNA, and ribosomal RNA</p> Signup and view all the answers

During DNA replication, only one strand of DNA serves as a template.

<p>False</p> Signup and view all the answers

How many nucleotides does a codon consist of?

<p>3</p> Signup and view all the answers

The anticodon AGA is complementary to the mRNA codon TCT.

<p>False</p> Signup and view all the answers

Study Notes

DNA and its Function

  • DNA stores genetic information in cells, essential for heredity and biological functions.
  • Functions like a book by storing, copying, and passing on information through generations.

Nucleotides and Base Pairing

  • A nucleotide in DNA consists of deoxyribose sugar, a phosphate group, and a nitrogenous base (e.g., cytosine).
  • Purines (adenine and guanine) are present in equal amounts to pyrimidines (cytosine and thymine) due to base pairing rules.

Key Discoveries in DNA Structure

  • Rosalind Franklin utilized X-ray diffraction to produce images that helped inform the structure of DNA.
  • James Watson and Francis Crick identified the DNA structure as a double helix.
  • Discovery sequence: Chargaff's nucleotide ratios → Franklin's X-ray photos → Watson and Crick's double helix model.

DNA Replication

  • Results in two DNA molecules, each containing one original and one newly synthesized strand.
  • Occurs before cell division in both prokaryotic and eukaryotic cells.
  • Example: A DNA strand with bases CTAGGT produces a complementary strand GATCCA.

RNA Basics

  • RNA differs from DNA, containing ribose sugar instead of deoxyribose.
  • Types of RNA: Messenger RNA (mRNA), Transfer RNA (tRNA), and Ribosomal RNA (rRNA) play roles in protein synthesis.
  • mRNA carries genetic information from DNA to the rest of the cell.

Transcription and Translation

  • Transcription produces RNA molecules that are complementary to DNA strands.
  • During translation, the mRNA code is used to synthesize proteins, guided by codons linked to specific amino acids determined by tRNA anticodons.

Genetic Code

  • 9 nucleotides are required to specify three amino acids, highlighting the relationship between codons and amino acids.
  • There are 64 possible codons but only 20 amino acids, meaning multiple codons can correspond to a single amino acid.

Mutations

  • A point mutation is a change involving a single nucleotide.
  • Chromosomal mutations include deletions (loss of information) and inversions (reordering of segments).
  • Most mutations have no noticeable effects on organisms' functioning.

Miscellaneous

  • The three types of RNA have distinct roles in protein synthesis and genetic expression.
  • Codons are groups of three nucleotides, fundamental to the genetic coding system.
  • The anticodon of tRNA must match the codon of mRNA for correct protein assembly, noting that RNA uses uracil instead of thymine.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Description

Test your knowledge of key concepts in Biology Chapter 12 with these flashcards. This quiz covers essential topics such as DNA structure, its functions, and the importance of nucleotide pairing. Strengthen your understanding and prepare for assessments with targeted questions.

More Like This

DNA Structure Flashcards
15 questions
ADN y su Estructura
10 questions

ADN y su Estructura

AdroitBinomial7587 avatar
AdroitBinomial7587
Prokaryotic Nucleoid and DNA Quiz
8 questions
Use Quizgecko on...
Browser
Browser