2.2.1 - 2.2.2 mutations, cell division, protein synthesis

Question 1

Prophase

Answer 1

• Chromosomes condense
• Nuclear envelope breaks down
• Centrosomes produce spindle fibers & migrate to opposite poles

Question 2

Metaphase

Answer 2

• Chromosomes line up at metaphase plate
• Centrosomes arrive at opposite poles

Question 3

Anaphase

Answer 3

• Protein holding together sister chromatids breaks down
• Spindle fibers attach to kinetochores and pull apart chromatids (now chromosomes)

Question 4

Telophase

Answer 4

• Chromosomes arrive at opposite poles
• Nuclear envelope forms around them
• Chromosomes de-condense

Question 5

Main functions of proteins

Answer 5

Cellular reactions, defense, building structures, transporting materials, coordinating cellular responses, & movement

Question 6

Proteins & cellular reactions

Answer 6

Proteins help break down food, build nucleic acids, & control cell division

Question 7

Proteins & defense

Answer 7

Proteins produce antibodies and fight substances like bacteria, viruses, and fungi

Question 8

Proteins & building structures

Answer 8

Proteins build collagen/elastin and keratin

Question 9

Proteins & transporting materials

Answer 9

Proteins help carry nutrients, gases, and waste (ie, proteins making up hemoglobin carrying oxygen)

Question 10

Proteins & coordinating cellular responses

Answer 10

Hormonal proteins maintain homeostasis
Sensory proteins help smell, taste, etc.

Question 11

Proteins & movement

Answer 11

Proteins help cells move

Question 12

Transcription steps

Answer 12

1) RNA Polymerase binds to area of gene called promoter
2) DNA strands unwind
3) RNA polymerase reads template strand and builds mRNA
4) RNA polymerase stops building when reaches stop sequence in gene
5) mRNA detaches from DNA & DNA closes back up
6) Pre-mRNA edited & when ready, leaves nucleus

Question 13

Translation steps

Answer 13

1) Correct amino acids are attached to tRNA molecules depending on the anticodon
2) Small ribosomal subunit attaches to mRNA
3) Ribosome finds start codon on MRNA & begins reading
4) tRNAs with matching anticodons arrive in ribosome
5) tRNAs leave behind amino acid and leave to get more amino acids
6) Ribosome shifts along mRNA strand to read more codons
7) The created amino acids join together through polypeptide bonds
8) Once done, the ribosome releases the finished polypeptide

Question 14

Sickle cell & mutations

Answer 14

Hemoglobin is made of 4 proteins. 1 protein is the hemoglobin subunit beta (HBB). The sickled form of the HBB protein is caused by a single adenine turning into a thymine in the gene that codes for HBB.