Protein Synthesis And Cell Life Cycl

Question 1

Nucleus

Answer 1

Cell’s control center, largest organelle

Question 2

Nuclear envelope

Answer 2

Double membrane around nucleus

Question 3

Nuclear pores

Answer 3

Communication passages

Question 4

Components of Nucleus: DNA

Answer 4

All info to build and run organisms

Question 5

Components of Nucleus: Nucleoplasm

Answer 5

FLUID containing ions, enzymes, nucleotides, some RNA

Question 6

Nuclear Matrix

Answer 6

Support filaments

Question 7

Nucleoli

Answer 7

Related to protein productions; made of RNA, enzymes, histones; synthesizes rRNA and ribosomal subunits

Question 8

Nucleosomes

Answer 8

DNA coiled around histones

Question 9

Chromatin

Answer 9

Loosely coiled DNA (cells not dividing)

Question 10

Chromosomes

Answer 10

Tightly coiled DNA (cells dividing)

Question 11

Gene

Answer 11

DNA instructions for one protein

Question 12

Genetic code

Answer 12

Sequence of bases

Question 13

Triplet code

Answer 13

3 bases = 1 amino acid

Question 14

Gene activation: uncoiling of DNA

Answer 14

Promoter, terminator

Question 15

Transcription

Answer 15

Copies instructions from DNA to mRNA (in nucleus)

Question 16

Transcription: RNA polymerase

Answer 16

Produces messenger RNA (mRNA)

Question 17

Translation

Answer 17

Ribosome reads mRNA, assembles into polypeptide chain, RNA -> protein

Question 18

3 steps of mRNA transcription

Answer 18

1. Gene activation
2. DNA to mRNA
3. RNA processing

Question 19

Gene activation

Answer 19

Uncoils DNA, removes histones
Start (promoter) and stop codes on DNA mark location of gene

Question 20

Gene activation: coding strand

Answer 20

Code for protein

Question 21

Gene activation: template strand

Answer 21

Used by RNA polymerase molecule

Question 22

DNA to mRNA

Answer 22

RNA polymerase transcribes DNA (reads code, binds nucleotides to form mRNA, mRNA duplicates DNA coiling strand)

Question 23

RNA Processing

Answer 23

mRNA detaches from DNA molecule
- introns removed, exons spliced together, codon

Question 24

Translation: mRNA moves

Answer 24

• from nucleus through nuclear pore
• to a ribosome in cytoplasm
• mRNA binds to ribosomal subunits
• tRNA delivers amino acids to mRNA

Question 25

Somatic cell: life cycle stages

Answer 25

1. DNA replication 2. Mitosis 3. Cytokinesis

Question 26

Cell Life Cycle: DNA replication

Answer 26

1. Helicase unwinds DNA strands 2. RNA Polymerase - promotes bonding, links nucleotides

Question 27

Interphase

Answer 27

Non dividing period

Question 28

Interphase: G-zero

Answer 28

Specialized cell functions only

Question 29

G1 phase

Answer 29

Cell growth, organelle duplication, protein synthesis

Question 30

S phase

Answer 30

DNA replication and histone synthesis

Question 31

G2 phase

Answer 31

Finishes protein synthesis and centrioles replication

Question 32

Mitosis

Answer 32

Divides duplicated DNA into two sets of chromosomes

Question 33

Kinetochore

Answer 33

Protein complex around centromere

Question 34

Cytokinesis

Answer 34

Division of cytoplasm (clevage, membrane closes)

Question 35

Slower mitotic rate

Answer 35

Longer cell life

Question 36

Rarely dividing cells

Answer 36

Muscle cells, neurons

Question 37

Skin and digestive tract

Answer 37

Exposed cells only live days or hours

Question 38

Increased cell division: internal factors

Answer 38

M-phase promoting factor, MPF

Question 39

Increased cell division: extracellular chemical factors

Answer 39

Growth factora

Question 40

Decreased cell division

Answer 40

Repressor genes, worn out telomeres

Question 41

Cancer develops in steps

Answer 41

Abnormal cell, primary tumor, metastasis, secondary tumor

Question 42

Tumor (neoplasm)

Answer 42

Enlarged mass of cells, abnormal cell growth + division

Question 43

Benign tumor

Answer 43

Contained, not life threatening unless large

Question 44

Malignant tumor

Answer 44

Spreads into surrounding tissues (invasion), starts new tumors (metastasis)

Question 45

Differentiation

Answer 45

Specializes, form tissues and turning off genes not needed by that cell