The fundamental unit of life

Question 1

What are the basic properties of cells?

Answer 1

-Alive
-Highly organized and complex
-Posses a genetic program
-can produce more of themselves
-Acquire and utilize energy
-Carry out a variety of chemical reactions
-Engage in mechanical activities
-Respond to stimuli
-Perform self-regulation
-Evolve

Question 2

Compare and contrast prokaryotic and eukaryotic cells

Answer 2

Similarities:
-Plasma membrane
-Cytoplasm
-DNA
-Ribosomes
-Flagella (some)

Differences:
Eukaryotes:
-Nuclues
-membrane-bound organelles
-Larger, complex
-Multi-cellular or unicellular
-DNA organized into chromosomes
-Larger genome
-Cell reproduction -mitosis/meiosis
-Plants, animals, fungi, protists

Prokaryotes:
-NO nuclues (has nucleoid)
-NO membrane-bound organelles
-Small, simple
-Unicellular
-DNA organized as long strand
-Small genome
-Cell reproduction -fission
-Bacteria, achaebacteria

Question 3

Describe mitosis in eukaryotes

Answer 3

-Complex process of cell division
-Chromosomes duplicated: condensed into compact structures
-Separated by elaborate microtubule-containing apparatus (mitotic spindle)
-Generates 2 identical daughter cells

Question 4

Describe cell reproduction in prokaryotes

Answer 4

-One copy of single chromosome
-Reproduce via binary fission
-No process comparable to meiosis/gamete formation/true fertilization (ie. is asexual)
-Conjugation (some): piece of DNA passed to another cell
-Incorporation of foreign DNA from environment: microbial evolution

Question 5

Describe locomotion in prokaryotes and eukaryotes

Answer 5

Prokaryotes:
-Relatively simple
-Flagellum:
-Thin protein filament
-Protrudes from the cell, rotates
-Rotation exerts pressure against surrounding fluid and propels cell

Eukaryotes:
-Flagellum
-Many protists, sperm cells
-Structurally and functionally more complex than prokaryotes

Question 6

What are archaea?

Answer 6

-Evolutionally related species to bacteria
-Live in extermely inhispitable envrionments “extremophiles”

Question 7

What are the different kinds of extremophiles?

Answer 7

Methanogens:
-convert CO2 and H2 into methane

Halophiles:
-++ salty environments
-Dead Sea, deep sea brine pools (5M MgCl2)

Acidophiles:
-pH as low as 0

Thermophiles:
-++ high temperatures

Hyperthermophiles:
-Ocean hypothermal vents
-121C (sterilize surgical instruments)

Question 8

Describe bacteria

Answer 8

-Live in every habitat on earth (i.e., rock layers)
-Includes smallest known cells (mycoplasma -only prokayote without cell wall)
-Cyanobacteria: cytoplasmic membranes -photosynthesis

Question 9

What are protists?

Answer 9

-Complex eukaryote
-Similar to a whole organism: sense the environment, trap food, expelling excess fluid, evade predators
-All within a single cell

Question 10

What are the model organisms in research?

Answer 10

-Non-human species, studied extensively
-Selected because of the properties of the organism and are easy to maintain

Prokaryote:
-E.Coli

Eukaryotes:
-Yeast
-Arabidopsis (plant)
-C. Elegan (worm)
-Drosophilia (fly)
-Mus Musculus (mouse)
-Zebrafish