7th science ch. 5 lesson 2

RNA contains which nitrogen bases.......

• adenine

• guanine

• cytosine

• thymine

• uracil

Which are the two types of RNA?

• messenger RNA

• transfer RNA

• gene RNA

• duplicate RNA

Protein synthesis takes place in the _______ of a cell.

• cytoplasm

• nucleus

• ribosome

• wall

There are _____ amino acids which can combine in different ways to form thousands of different proteins.

• 20

• 50

• 25

• 35

Proteins help determine what you look like.

• true

• false

______ help determine the size, shape, color, and other traits of an organism by triggering cellular processes.

• Proteins

• Bacteria

• Chromosomes

• ribosomes

There are _____ steps of protein synthesis.

• 5

• 3

• 10

• 6

Which is the correct order of the five steps of protein synthesis?

• 1. mRNA enters the cytoplasm (DNA unzips)

  2. ribosomes attach to mRNA

  3. tRNA attaches to mRNA

  4. amino acids join in the ribosome

  5. protein chain forms

• 1. protein chain forms

  2. ribosomes attach to mRNA

  3. tRNA attaches to mRNA

  4. mRNA enters the cytoplasm (DNA unzips)

  5. amino acids join in the ribosome

• 1. tRNA attaches to mRNA

  2.. mRNA enters the cytoplasm (DNA unzips)

  3.. amino acids join in the ribosome

  4. protein chain forms

  5. ribosomes attach to mRNA

• 1. mRNA enters the cytoplasm (DNA unzips)

  2. amino acids join in the ribosome

  3. ribosomes attach to mRNA

  4. protein chain forms

  5. tRNA attaches to mRNA

DNA unzips between its base pairs. Then one of the strands of DNA directs the production of a strand of mRNA. To form the RNA strand, RNA bases pair up with the DNA bases.

• mRNA enters the cytoplasm

• ribosomes attach to mRNA

• tRNA attaches to mRNA

• amino acids join in the ribosome

• protein chain forms

A ribosome attaches to mRNA in the cytoplasm. The mRNA provides the code for the protein that will be made.

• mRNA enters the cytoplasm

• ribosomes attach to mRNA

• tRNA attaches to mRNA

• amino acids join in the ribosome

• protein chain forms