Chapter 4

Question 1

Spell out these abbreviations:
ECF | ICF | ATP | ADP | DNA | RNA

Answer 1

• Extracellular Fluid
• Intracellular Fluid
• Adenosine Triphosphate
• Adenosine Diphosphate
• Deoxyribonucleic Acid
• Ribonucleic Acid

Question 2

What are the three types of RNA?

Answer 2

• messenger RNA (mRNA)
  – ribosomal RNA (rRNA)
  – transfer RNA (tRNA)

Question 3

What is Transcription? How does it occur?

Answer 3

Transcription – copying genetic instructions from DNA to RNA

• DNA too large to leave nucleus and participate directly in cytoplasmic
  protein synthesis
  – necessary to make a small mRNA copy that can migrate through a nuclear pore into the cytoplasm

• RNA Polymerase – enzyme that binds to the DNA and assembles the mRNA

Question 4

What is Translation?

Answer 4

translation – the process that converts the language of nucleotides into the language of amino acids

• ribosomes - translate sequence of nucleotides into the sequence of amino acids
– occur mainly in cytosol, on surface of rough ER, and nuclear envelope
– the ribosome consists of two granular subunits, large and small

• each ribosome is made of several rRNA and enzyme molecules

Question 5

Give the entire summary of protein synthesis:

Answer 5

process of protein synthesis
– DNA -> mRNA -> protein

• transcription – step from DNA to mRNA – occurs in the nucleus where DNA is located

• translation – step from mRNA to protein – most occurs in cytoplasm

– 15-20% of proteins are synthesized in the nucleus

Question 6

What are the 4 phases of mitosis?

Answer 6

PMAT (Prophase, Metaphase, Anaphase, Telophase)

Question 7

What is Modern Cell Theory?

Answer 7

• All organisms composed of cells and cell products.
• Cell is the simplest structural and functional unit of life.
  – cells are alive
• An organism’s structure and functions are due to the activities
  of its cells.
• Cells come only from preexisting cells, not from nonliving matter.
  – therefore, all life traces its ancestry to the same original cells
• Cells of all species have many fundamental similarities in their
  chemical composition and metabolic mechanisms.

Question 8

What did Louis Pasteur establish?

Answer 8

Louis Pasteur established beyond any reasonable
doubt that ‘cells arise only from other cells’

Question 9

What are the two types of tumors? Characteristics?

Answer 9

• benign tumor
– slow growth
– contained in fibrous capsule
– will not metastasize
– usually easy to treat

• malignant tumor – called cancer
– fast growing
– metastasize – give off cells that seed the growth of multiple tumors elsewhere

Question 10

What is tumor angiogenesis?

Answer 10

tumor angiogenesis – ingrowth of blood vessels stimulated by energy-hungry tumors

Question 11

What is a carcinoma (cancer)?

Answer 11

carcinomas – originate in epithelial tissue

Question 12

What is a lymphoma (cancer)?

Answer 12

lymphomas – originate in lymph nodes

Question 13

What is a melanoma (cancer)?

Answer 13

melanomas – originate in pigment cells of epidermis (melanocytes)

Question 14

What is a leukemia (cancer)?

Answer 14

leukemias – in blood forming tissues

Question 15

What is a sarcoma (cancer)?

Answer 15

sarcomas – in bone, other connective tissue, or muscle

Question 16

What is a carcinogen?

Answer 16

carcinogen – environmental cancer-causing agents

Question 17

Compare haploid vs diploid cells

Answer 17

• diploid – any cell with 23 pairs of chromosomes (somatic cells)
• haploid – contain half as many chromosomes as somatic cells – sperm
  and egg cells (germ cells)
  • fertilization restores diploid number to the fertilized egg and the somatic
  cells arise from it.

Question 18

Each DNA nucleotide is made up of:

Answer 18

Each nucleotide consists of
– one sugar - deoxyribose
– one phosphate group
– one nitrogenous base [Either pyrimidine (single carbon-nitrogen
ring) or purine (double ring)]

Question 19

RNA is:

Answer 19

one nucleotide chain (not a double helix as DNA)
• ribose replaces deoxyribose as the sugar
• uracil replaces thymine as a nitrogenous base
• Essential function
– interprets code in DNA
– uses those instructions for protein synthesis
– leaves nucleus and functions in cytoplasm

Question 20

Nitrogenous bases are United by:

Answer 20

Hydrogen bonds

Question 21

Explain the Law of Complementary Base Pairing:

Answer 21

– a purine on one backbone with a
pyrimidine on the other
– A – T two hydrogen bonds
– C – G three hydrogen bonds
• DNA base pairing
– A – T
– C – G
• Law of Complementary Base
Pairing
– one strand determines base
sequence of other

Question 22

What are the two types of nitrogenous bases in DNA, how do they line up?

Answer 22

Purines - double ring (Pure As Gold, we want double the gold)
– Adenine (A)
– Guanine (G)
• Pyrimidines - single
ring (CUT Pie, only one pie so you don’t get fat)
– Cytosine (C)
– Thymine (T)

• DNA bases -
A – T two hydrogen bonds
C – G three hydrogen bonds

a purine on one backbone with a
pyrimidine on the other