BIOL HW CH 1
Which practices in agriculture and animal domestication demonstrate a rudimentary understanding of heredity and genetics?
- Primitive societies were more likely to kill wolves that were too aggressive and keep the less aggressive ones as pets and hunting companions. - Farmers planted seeds from trees that produced the largest, sweetest fruits and not from trees that produced the smallest or inedible fruits. - Nomads selected the most muscular cattle for breeding.
Suppose that life exists elsewhere in the universe. All life must contain some type of genetic information, but alien genomes might not consist of nucleic acids or have the same features as those found in the genomes of life on Earth. What might be the common features of all genomes, no matter where they exist?
- The ability to replicate the genetic information accurately for the next generation - The ability to store the entire set of information an organism needs for reproduction and development
Which of the statements are reasons why rhinoceroses would be a poor choice as model organisms for studying ovarian cancer?
- They are inappropriate for experimental manipulation because they are an endangered species. - They are needlessly large when smaller, more easily handled organisms, such as mice, are available. - They produce very few offspring at a time and thus require a lot of time to collect meaningful data.
Pioneering work in the field of genetics began prior to the 20th century. However, much of the early work relied only upon simple observation. Select the genetics concepts that were discovered before the year 1900.
- calculation of Mendelian inheritance - theory of natural selection
Which of the statements are ways that modern geneticists are addressing medical, social, or industrial problems?
- developing genetic tests for conditions so that patients can receive appropriate treatment - studying bacterial genetics to learn how to control the spread of infectious diseases -improving the yield of agricultural crops through genetic modification
Cell theory began to develop in 1839, following the research of Matthias Schleiden and Theodor Schwann into plant and animal tissues. Both the botanist Schleiden and the physiologist Schwann noticed that every organism they viewed under a microscope, whether plant or animal, was composed of cells. Their observations that all living species are made up of one or more cells led to the early formation of cell theory. Which tenet of cell theory is described by the paragraph about the historical observations of cells?
ALL organisms are composed of one or more cells
What are the multiple forms of one gene called?
Alleles
Which organism would not be considered a useful model genetic organism?
Bos taurus (the cow)
Pangenesis concept
Cells in different tides have unique genetic codes that are transferred to the gonads to produce gametes
Who was a nineteenth‑century biologist who put forth the theory of evolution through natural selection and published his idea in the book entitled On the Origin of Species?
Charles Darwin
Which statement describes the central dogma of biology?
DNA is transcribed into RNA. RNA is translated into an amino acid sequence.
Which statement identifies what The Green Revolution relied upon genetic applications to accomplish?
Expands the world's food production
Match each description to the term it defines.
Gene - a chromosomal region that codes for a functional transcript - a functional unit of heredity Allele - an alternative forms of a particular gene Chromosome - threadlike DNA molecules are visible during mitosis - large genetic element that carries genes essential to cellular function
Preformationism
Genetic information is inherited form one parent or the other, not both
Who discovered the basic principles of heredity?
Gregor Mendel
Match the current applications to the appropriate branch of genetics. Not all applications will be placed.
Hereditary - researching gene transmission to understand disease - tracing pedigrees to determine patterns of gene transmission within a family Population - calculating genotypes frequencies to understand phenotype changes in a population Molecular- expressing exogenous transgenes to understand function - determining how point mutations affect gene function
Given observations of a family, identify the best‑supported conclusion about genetic versus environmental trait determination.
Identical twins separated at birth and raised in different parts of the country both have a severe form of asthma that neither biological parent has. Conclusion: genetic factors caused the asthma.
Classify the following traits as inherited or acquired:
Inherited: brown eyes, attached earlobes, cystic fibrosis, face shape Acquired: ability to read, muscle mass gained from strength training, small stature due for malnourishment, fetal alcohol syndrome
Classify each statement as true for either the concept of pangenesis or the germ‑plasm theory.
Pangenesis - offspring inherit genetic information from throughout their parents' bodies- different tissues contain only their own genetic information Germ-plasm theory - all cells contain complete genetic information - offsprings inherit genetic information from their parents' reproductive cells only
Classify descriptions as pertaining to prokaryotic cells, eukaryotic cells, or both.
Prokaryotes - lack of nucleus - localized genome in the cytoplasm Eukaryotes - include algae - contain chloroplasts both- have a cytoplasm
What characteristic makes prokaryotic cells different from eukaryotic cells?
Prokaryotic cells do not contain membrane‑bound organelles.
Germ-plasm theory
Reproductive cells have complete genetic codes for their species
The blending inheritance theory differs from the concept of preformationism. What does the blending inheritance theory state and how is this different from preformationism?
The egg and sperm contain genetic material that mixes upon conception to produce an intermediate phenotype in the offspring.
What is the complete set of genetic instructions for an organism?
a genome
Which characteristic would not be considered useful for a model genetic organism?
a long generation time
Which genetic condition is found at an unexpectedly high frequency among the Hopi Native Americans?
albinism
What is the most inclusive definition of a model organism (model system)?
an organism with a biological system that is representative of the same system in other organisms
What are the structures in a cell that group genes together, are composed of chromatin (DNA and protein), and become visible under a light microscope during mitosis?
chromosomes
Classify each action as belonging to genetics, genomics, or both.
genetics - study individual gene function - control gene expression genomics - study many genes - assemble a map of all chromosomes - use whole-organism approach both - study DNA
What concept proposes that traits acquired in a person's lifetime become incorporated into that person's hereditary information and are passed on to offspring?
inheritance of acquired characteristics
What process involves the separation of chromosomes in the division of somatic, nonsex, cells?
mitosis
The study of the chemical nature of the gene, and how genetic information is replicated and expressed, is part of what division of genetics?
molecular genetics
What early concept of heredity proposed that genetic information in the form of particles called gemmules travels from different parts of the body to reproductive organs?
pangenesis
Which of these describes a genome?
the collection of genetic material in a cell or organism
In what way have humans been applying the principles of heredity for millennia?
the domestication of plants and animals
How does the structure of DNA encode genetic information?
the sequence of bases