Bio Final Module B

What is the relationship between chromosomes, genes, and nuclei?

chromosomes: chromosomes are found in nuclei genes: genes are found on chromosomes nuclei: where chromosomes are found

Down syndrome is a genetic disorder caused by the presence of an extra chromosome in the body cells of humans. What causes this extra chromosome to be present?

An error in meiotic cell division

To produce large tomatoes that are resistant to cracking and splitting, some seed companies use the pollen from one variety of tomato plant to fertilize a different variety of tomato plant. What is this process an example of?

Selective breeding

When is extinction of a species most likely to occur?

When environmental conditions change and the members of the species lack adaptive traits to survive and reproduce

What is the relationship between DNA, genes, alleles and chromosomes?

A chromosome is a DNA molecule that contains alleles which are forms of a gene

What is the relationship between cells, DNA, and proteins?

Cells contain DNA that controls the production of proteins

which structures are analogous: bat, dolphin, moth, bird?

bat, moth, bird

A species of bird known as Bird of Paradise has been observed in the jungles of New Guinea. The males shake their bodies and sometimes hang upside down to show off their bright colors and long feathers to attract females. Females usually mate with the "flashiest" males. These observations can be used to support the concept that:

behaviors that lead to reproductive success have evolved

3. A difference between prokaryotes and eukaryotes is seen in the organization of heir genetic material. a. Discuss the organization of the genetic material in prokaryotes and eukaryotes. b. Contrast all of the following activities in prokaryotes and eukaryotes: - DNA replication - transcription OR translation - gene regulation - cell division

genetic material in eukaryotes is tightly packed and can be found in the nucleus. Prokaryotes do not have a nucleus so the genetic material is free floating in the cytoplasm. DNA replication in prokaryotes requires more enzymes and occurs at a much faster rate than eukaryotic replication transcription/translation in prokaryotes occur at the same time. In eukaryotes transcription takes place in the nucleus and translation takes place in the cytoplasm Gene regulation in prokaryotes occurs in the cytoplasm while in eukaryotes it occurs in both the nucleus and cytoplasm Cell division in prokaryotes is called binary fission and it is much simpler than cell division in eukaryotes because prokaryotes lack many membrane bound organelles.

Crossing over

the origin of new combinations of traits in offspring

If an individual has one iA and one iB allele, what type of inheritance pattern would the genotype represent?

Co-dominance

In sexually reproducing species, the number of chromosomes in a zygote is diploid as a direct result of what 2 processes?

Meiosis and fertilization

A point mutation occurs during DNA replication; more specifically, a substitution of an A for a T occurs. There is no change in the amino acid sequence of the polypeptide. Which type of mutation is this?

silent

2. Scientists seeking to determine which molecule is responsible for the transmission of characteristics from one generation to the next knew that the molecules must (1) copy itself precisely (2) be stable but able to be changed and (3) be complex enough to determine the organism's phenotype. a. Explain how DNA meets each of the three criteria stated above. b. Select one of the criteria stated above and describe experimental evidence

DNA is copied precisely because the two strands have complementary base pairs DNA is a complex substance made of sugars, proteins, and bonds which provides stability. However, when replication occurs, errors can be made causing the strand to change. DNA is complex enough to determine an organism's phenotype because their are many combinations that can make up a unique genetic code. No one has DNA that is alike. Hershey and Chase performed a series of experiments and discovered that DNA is genetic material. They discovered that radioactive bacteriophages effected the DNA of later generations which proves that DNA replicates precisely

DNA replication and protein synthesis occurs in a cell. What is the correct order of the events involved for the genetic information to contribute to phenotypic expression?

DNA is replication mRNA is produced joining of amino acids in sequence appearance of characteristics

What is true of both mitosis and meiosis?

DNA replication occurs before the division of the nucleus in both processes.

Although all the cells of a human develop from one fertilized egg, the human is born with many different types of cells. Why does this happen?

Developing cells may express different parts of their identical genetic instructions

A polypeptide is made at a ribosome attached to the endoplasmic reticulum (ER). Trace the pathway it follows to leave the cell.

Enters through rough ER packaged in a vesicle enters the Golgi apparatus packed in vesicles exported from the cell

1. The unit of genetic organization in all living organisms is the chromosome. a. Describe the structure and function of the parts of a eukaryotic chromosome. You may wish to include a diagram as part of your description. b. Describe the adaptive (evolutionary) significance of organizing genes into chromosomes. c. How does the function and structure of the chromosome differ in prokaryotes

Eukaryotic chromosomes consist of a DNA-protein complex that is organized in a compact manner which permits the large amount of DNA to be stored in the nucleus of the cell. The adaptive evolutionary significance is to simplify the process of dividing the genes up during reproduction because all genes are in the same general area instead of free floating Chromosomes in prokaryotic cells are not contained in a nucleus. Prokaryotic chromosomes are circular while eukaryotic chromosomes are tightly bound together.

Mitosis and meiosis are processes by which animal and plant cells divide. Which is a difference between mitosis and meiosis?

Mitosis produces genetically identical daughter cells

Which process is described below? "Messenger RNA is bound by the ribosome tRNA molecules are coded for by the mRNA tRNA molecules carry specific amino acids to the ribosomes the amino acids are added to a growing chain which becomes a polypeptide."

translation