A&P 1 Chapter 3 (Lecture) [The Cell, Part 5]

Question 1

Forms of DNA

Answer 1

• Nucleosome
• Chromatin
• Chromosomes

Question 2

Protein to package DNA

Answer 2

Histone

Question 3

Central Dogma Steps

Answer 3

1. Activate Gene
2. Produce mRNA (transcription)
3. Edit mRNA (RNA processing)
4. Read mRNA and assemble protein (Translation)

Question 4

Gene Activation

Answer 4

• DNA uncoils and histones are removed
• Start sequence is exposed for RNA polymerase to attach (known as TATA box)

Question 5

Transcription

Answer 5

• RNA polymerase runs along the DNA sequence. Does the following:
  
  • Separates DNA strands
    
    • Sense strand (actual gene)
    • Non- Sense Strand
  • Reads non-sense strand to make a copy of the sense strand.

Question 6

RNA Processing

Answer 6

• Removal of Introns
  
  • Unneeded base sequence
• Splicing of Exons
  
  • Portion of mRNA coding for sequence of amino acids in a polypeptide

Question 7

Translation

Answer 7

• mRNA leaves nucleus and binds to ribosomes at start codon
• tRNA delivers amino acids
  
  • Anticodon = three RNA nucleotides complementary to mRNA codon
• Ribosomes form peptide bond between amino acid
• Continues process until it reaches a stop codon.

Question 8

Structures of the Nucleus

Answer 8

• Nuclear Envelope
• Nuclear Pores
• Nucleoplasm
• Nucleolus

Question 9

Nuclear Envelope

Answer 9

• Double Membrane
• Perinuclear Space (In between membranes)
• Nuclear Pores

Question 10

Nuclear Pores

Answer 10

Account for about 10% of the surface of the nucleus, are passageways that permit chemical communication between the nucleus and the cytosol. Proteins at the pores regulate the movement of ions and small molecules, and neither proteins nor DNA can freely cross the nuclear envelope.

Question 11

Nucleoplasm

Answer 11

• Fluid inside nucleus
  
  • DNA
  • RNA
  • Nucleotides
  • Enzymes
  • Ions

Question 12

Nucleolus

Answer 12

Site of ribosomal RNA synthesis and ribosomal subunit assembly

Question 13

Nucleosome

Answer 13

DNA coiled around histones (proteins)

Question 14

Chromatin

Answer 14

Loosely coiled DNA, no protein

Question 15

Chromosomes

Answer 15

Tightly coiled DNA, no proteins

Question 16

The Cell Cycle

Answer 16

• Interphase
  
  • G1 (Growth)
  • S Phase (Synthesis)
  • G2 (Growth)
• Mitosis
  
  • Prophase
  • Metaphase
  • Anaphase
  • Telophase

Question 17

Interphase

Answer 17

• G1
  
  • Normal cell functions
  • Cell growth
  • Protein synthesis
• S Phase
  
  • DNA replication
• G2
  
  • Proteins synthesis
  • Mitosis preparation

Question 18

Prophase

Answer 18

• Chromosomes become visible
• Nuclear envelope and nucleolis disappears
• Spindle Apparatus begins to form
• Centrioles begin to separate

Question 19

Metaphase

Answer 19

• Chromosomes line up at metaphase plate
• Centrioles at opposite poles
• Spindle apparatus fully formed
  
  • Each chromatid attached to spindle fiber by its kinetochore.

Question 20

Anaphase

Answer 20

• Chromatids separate
  
  • Move toward opposite poles
• Cell elongates
• Two indentical sets of chromosomes (one at each pole) at end of anaphase

Question 21

Telophase

Answer 21

• Chromosomes uncondense
• Nuclear envelopes reform
• Nucleoli reform
• Cleavage furrow forms

Question 22

DNA Replication

Answer 22

• DNA strands separate
• DNA polymerases run along each strand
• DNA polymerases use free nucleotides to produce complementary strand
• Process happens at multiple places along DNA strands

Question 23

Answer 23

Prophase

Question 24

Answer 24

Metaphase

Question 25

Answer 25

Anaphase

Question 26

Answer 26

Telophase