Intro-Ch1-P9-14End Flashcards
Who described the cell nucleus in 1833?
Robert Brown
Who proposed the concept of cell theory in 1839?
Matthias Jacob Schleiden and Theodor Schwann
What is cell theory?
All life is composed of cells, cells arise only from preexisting cells and the cell is the fundamental unit of structure and function in living organisms.
Who came up with theory of evolution through natural selection?
Charles Darwin in On the Origin of Species in 1859
Who disproved the notion of inheritance of acquired characteristics? And how did he prove it?
August Weismann.He cut off the tails of 22 consecutive generations of mice and showed that the tail length did not change in the young. Did this experiment during the late 19th century.
Germ-plasm theory?
August Weismann proposed this, which holds that the cells in the reproductive organs carry a complete set of genetic information that is passed to the egg and sperm.
Who proposed that the units of inheritance are located on chromosomes? And what year did this occur?
Walter Sutton in 1902
Who described the three-dimensional structure of DNA? And what year was this?
James Watson, Francis Crick, Maurice Wilkins and Rosalind Franklin. In 1953.
Mendelian inheritance?
Traits are inherited in accord with defined principles. True.
What has DNA traced the cat back to?
A panther like cat living in Southeast Asia 11 million years ago.
What is Proteomics?
It is the large-scale study of proteins, particularly their structures and functions.
What is Bioinformatics?
It is an interdisciplinary field that develops and improves upon methods for storing, retrieving, organizing and analyzing biological data. A major activity in bioinformatics is to develop software tools to generate useful biological knowledge.
How many years ago did humans first apply genetics to the domestication of plants and animals?
10,000 to 12,000 years ago.
Difference between prokaryotic and eukaryotic cells?
Prokaryotic cells lack a nuclear membrane and possess no membrane bound cell organelles, whereas the eukaryotic cells are more complex possessing a nucleus and membrane bound organelles such as chloroplasts and mitochondria.
Allele?
A gene that specifies a characteristic may exist in several forms called alleles. For example, a gene for coat colour in cats may exist as an allele that encodes black fur or as an allele that encodes orange fur.
What is phenotype?
It is the composite of an organism’s observable characteristics or traits, such as its morphology, development, biochemical or physiological properties, phenology, behavior, and products of behavior (such as a bird’s nest). Phenotypes result from the expression of an organism’s genes as well as the influence of environmental factors and the interactions between the two.
From the text book: It is the genetic information that an individual organism possesses.
Genetic information is carried in?
DNA (deoxyribonucleic acid) and RNA (ribonucleic acid)
Describe nucleic acids
They are polymers (repeating structural units) of repeating units called nucleotides. Each nucleotide consists of a sugar, a phosphate and a nitrogenous base.
What are the four types of nitrogenous bases in DNA? Explain a little?
- Adenine (A)
- Cytosine (C)
- Guanine (G)
- Thymine (T)
The sequence of these bases encodes genetic information. DNA consists of two complimentary nucleotide strands. Most organisms carry their genetic information in DNA but a few viruses carry it in RNA.
What are the four nitrogenous bases of RNA?
- Adenine (A)
- Cytosine (C)
- Guanine (G)
- Uracil (U)
Chromosomes are …..?
the vehicles of genetic information within a cell. Chromosomes consist of DNA and associated proteins.
How many chromosomes do the cells of each organism have?
All different. Ie bacterial cells normally have one chromsome, human cells possess 46 and pigeons possess 80. Each chromosome carries a large number of genes.
Chromosomes separate through the processes of …..?
mitosis and meiosis
Mitosis?
Is the separation of chromosomes in the division of somatic (non-sex) cells.
Meiosis?
Is the pairing and separation of chromosomes in the division of sex cells to produce gametes (reproductive cells).
Genetic information is transferred from… ?
DNA to RNA to the amino acid sequence of a protein.
Mutations are?
Permanent changes in genetic information that can be passed from cell to cell or from parent to offspring. Gene mutations affect the genetic information of only a single gene while chromosome mutations alter the number or the structure of chromosomes and therefore usually affect many genes.
