4.1 DNA, Genes, and Chromosomes

• The sequence of bases along DNA forms the genetic code
• What is a gene?

  Segment of DNA
• Match the DNA component with its detail:

  Deoxyribose Sugar ↔️ Forms the backbone of DNA

  Nitrogenous Bases ↔️ A, T, C, G

  Phosphate Group ↔️ Links nucleotides
• Which sex chromosome determines male characteristics?

  Y chromosome
• The Y chromosome is responsible for determining male sex characteristics
• Steps in DNA replication

  1️⃣ DNA helicase creates a replication fork

  2️⃣ DNA polymerase synthesizes new strands

  3️⃣ DNA ligase joins Okazaki fragments
• Which nitrogenous base pairs with guanine in DNA?

  Cytosine
• DNA is a single-stranded molecule.

  False
• In DNA, adenine pairs with thymine
• Arrange the types of chromosomes in order of their function:

  1️⃣ Autosomes (numbered chromosomes)

  2️⃣ Sex chromosomes (X and Y)
• Chromosomes are composed of DNA tightly coiled around proteins called histones
• Match the type of chromosome with its primary function:

  Autosomes ↔️ Control non-sex characteristics

  Sex chromosomes ↔️ Determine sex
• DNA replication is a semiconservative
• DNA ligase joins Okazaki fragments on the lagging strand.

  True
• The nitrogenous bases in DNA pair through hydrogen bonds
• Match the DNA component with its function:

  Deoxyribose Sugar ↔️ Forms the backbone of DNA

  Phosphate Group ↔️ Links nucleotides

  Nitrogenous Bases ↔️ Encode genetic instructions
• DNA stores genetic information through its double helix structure.

  True
• Hydrogen bonds link complementary base pairs in DNA.

  True
• Chromosomes are composed of a single, double-stranded DNA molecule tightly coiled
• In humans, females have XX sex chromosomes, while males have XY
• DNA replication is a semiconservative process.
• Match the process with its location:

  Transcription ↔️ Nucleus

  Translation ↔️ Cytoplasm
• Amino acids are linked during translation to form a protein.

  True
• tRNA carries specific amino acids to the ribosome.
• Gene expression begins with the transcription of DNA into mRNA
• Gene regulation determines when and how much of a gene product is made.

  True
• What is the primary function of DNA?

  Genetic instructions
• What is a gene?

  Segment of DNA
• What does DNA stand for?

  Deoxyribonucleic acid
• Match the nucleotide component with its description:

  Sugar ↔️ Deoxyribose

  Nitrogenous Base ↔️ A, T, C, G

  Phosphate ↔️ Attaches to the sugar
• Hydrogen bonds hold DNA strands together.

  True
• Males have two X chromosomes.

  False
• Autosomes are directly involved in determining sex.

  False
• Females typically have two X chromosomes, while males have one X and one Y
• What enzyme creates the replication fork during DNA replication?

  DNA helicase
• DNA is a double-stranded molecule composed of nucleotides
• A gene contains both coding and non-coding regions.


  True
• What forms the backbone of DNA?

  Deoxyribose sugar
• What are the four nitrogenous bases found in DNA?

  A, T, C, G
• Chromosomes ensure efficient storage and transmission of genetic information.


  True