Intro To The Living Cell

Question 1

Which Dutch draper and hobby microscopist was the first person to ever see individual living cells?

Answer 1

Antonie van Leeuwenhoek (1632-1723)

Question 2

All cells on earth store their hereditary information in what form?

Answer 2

Deoxyribonucleic acid (DNA)

Question 3

What term is used in reference to the copying of genetic information from DNA to RNA?

Answer 3

Transcription

Question 4

What term is used in reference to the copying of genetic information from RNA to protein?

Answer 4

Translation

Question 5

Apart from water, which makes up about 70% of tissues, what is the most abundant component of cells by mass?

Answer 5

Protein (18%)

Question 6

Nucleic acids are polymers of what type of chemical building blocks?

Answer 6

Nucleotides

Question 7

Proteins are polymers of what type of chemical building blocks?

Answer 7

Amino acids

Question 8

Rudolf Schoenheimer’s concept of cells as a “pattern in flux” refers to what feature of living cells?

Answer 8

The components of cells and tissues are constantly being replaced

Question 9

Define a living cell

Answer 9

The fundamental unit of all living things. Cells take surroundings and make copies of themselves

Question 10

State the range of cell sizes, from the smallest to the largest known cells

Answer 10

Small cells: 0.3 micrometers, 10^-4 grams e.g. mycoplasma genitalium
Big cell: 20cm, 2kg e.g. ostrich egg
Fancy cell: 100 micrometer e.g. diatom

Question 11

Discuss the key universal features of all living cells

Answer 11

Plasma membrane
Exchange of molecules with surroundings
Communication
Genetic information stored as DNA
Gene expression
Protein synthesis
Organelles of eukaryotic cells
Life as a ‘pattern in flux’
Evolution from a common ancestor

Question 12

Recall the organelles of eukaryotic cells

Answer 12

• plasma membrane
• nucleus
• nucleolus
• ribosomes
• cytoplasm
• ribosomes
• vesicles
• RER
• SER
• ER
• mitochondria
• chloroplasts (plants)
• vacuole (plants)
• cell wall (plants)
• lysosomes

Question 13

Describe in a schematic manner the structure of DNA, RNA and proteins

Answer 13

• DNA has a double helix with complementary base pairings as 2 antiparallel polynucleotide chains
• primary; DNA sequencing, secondary; helical structure, tertiary; DNA supercoiling, quaternary; interlocked chromosomes
• for RNA base uracil replaces thymine

Question 14

Explain in broad outline the steps by which genetic information in DNA is transcribed into RNA and then translated into protein

Answer 14

• synthesis of RNA molecule complementary to the DNA template but identical to the coding strand, no primer needed
• mRNA transported out of nucleus and ribosome directs protein synthesis, each codon interacts with anticodon of specific tRNA

Question 15

Explain the concept of life as “a pattern in flux”

Answer 15

• cells constantly being exchanged/turnover discovered by Schoenheimer
• Molecules in food are in cooperated in our tissue - constitutional elements
• cells divide and die and replaced eg red blood cell by differentiation

Question 16

Define the concept of homeostasis

Answer 16

The ability or tendency of an organism or cell to maintain internal equilibrium by adjusting its physiological processes eg negative feedback