Unit 1 Flashcards
(37 cards)
The feature that most clearly separates eukaryotes from prokaryotes is the presence of … in eukaryotic cells?
A nucleus
Cytoplasmic organelles are…
Absent in prokaryotic cells and present in eukaryotic cells
Eukaryotic chromosomes contain which type of DNA molecule?
Multiple linear
In Stanley Millers’ experiment, Applied electrical sparks to a reducing atmosphere of methane, ammonia, water and hydrogen showed that under these conditions
Amino acids can form
Which energy-producing process is thought to come first during cellular evolution?
Glycolysis
At the time life arose on earth, our atmosphere contained all of the following (H2, N2, H2S & H2O) except…
O2
Organisms that evolved the ability to use H2O as donor of electrons and hydrogen for the photosynthesis conversion of CO2 to organic compounds, radically changed earth by producing
O2
RNA is believed to have been the initial genetic system because it can
Catalyse the polymerisation of nucleotides into another RNA strand
The initial importance of a membrane enclosing self-replicating RNA molecules and associated proteins was that it
Maintained these molecules as a unit capable of reproduction and evolution
The bacterial genome is located in a portion of the cell called the
Nucleoid
Eukaryotic cell nuclei contain genes that are
Partly archaebacterial and partly eubacterial in origin
Organelles such as mitochondria and chloroplasts are thought to have originated in eukaryotic cells via a process called
Endosymbiosis
Mitochondria and chloroplasts resemble bacteria in that they
- Have their own DNA
- Have their own Ribosomes
- Reproduce by simple division into two
Which of the following is a colonial organism closely related to the evolutionary precursors of present-day plants?
Volvox
The human body is composed of more than how many different types of cells?
200
E. coli is a useful model System for molecular biology Studies because
- It has a small genome
- It reproduces rapidly
- mutants can be isolated easily from culture dishes
- It has simple nutritional requirements
A yeast cell divides in culture about every
2 hours
How how many genes does the yeast nuclear genome have?
6000
The adult nematode worm Caenorhabditis elegans consists of how many somatic cells?
959
The simplicity and clarity of Caenorhabditis elegans allowed researchers to
trace the developmental lineages of all cells in the adult
Drosophila melanogaster was the organism of choice for the study of
Animal genetics
Studies on which experimental organism led to the discovery of the gene controlling the development of the animal body plan?
Drosophila melanogaster
Arabidopsis thaliana is a model organism for studying the molecular biology of
Plants
Which fish is proving to be a useful model organism for the study of vertebrate development?
Zebrafish
