Abnormal Motor Proteins Cause Kartagener Syndrome An abnormal form of a motor protein called dynein causes Kartagener syndrome, a genetic disorder characterized by chronic sinus and lung infections. Biofilms form in the thick mucus that collects in the airways, and the resulting bacterial activities and inflammation damage tissues.
Affected men can produce sperm but are infertile. Some have become fathers after a doctor injects their sperm cells directly into eggs. Review FIGURE 4.21 and FIQURE 4.24, then explain how abnormal dynein could cause the observed effects.
FIGURE 4.24 Cross-section of the flagellum of a sperm cell from A a human male affected by Kartagener syndrome and B an unaffected male.
To explain: How abnormal dynein could cause Kartagener syndrome and male infertility.
Introduction: Kartagener syndrome is an autosomal recessive genetic condition characterized by ciliary motility disorder. Cilia are hair-like structures lining the mucus membranes of nose, lungs, and sinuses. In Kartagener syndrome, the cilia do not move properly and defects are found in dynein (a component of cilia) arms. This results in the abnormal morphology of sperm tails and bronchial cilia.
Explanation of Solution
Refer to Fig. 4.20, “How eukaryotic flagella and cilia move” in the textbook. Flagella and ciliary movements are provided by motor protein dynein attached to the nine microtubules arranged in a circle. Abnormality in dynein arms causes Kartagener syndrome. Refer to Fig. 4.24, “Cross-section of a sperm cell from A. a human male affected by Kartagener syndrome and B. an unaffected male” in the textbook. The lack of dynein arms results in the abnormal morphology of sperm tails and bronchial cilia causing lung infections, chronic sinus, and infertility. Men with Kartagener syndrome are infertile but they produce sperms. They are infertile because defected dynein would affect the movement of flagella and cilia. As a result, there would be abnormal sperm motility and it would not be able to swim normally for fertilization.
Want to see more full solutions like this?
Chapter 4 Solutions
Biology: The Unity and Diversity of Life (MindTap Course List)
- All of the specialized somatic cells of multicellular organisms _________. Select one: contain less genetic material than less specialized cells of the same organism. develop through mutation from less specialized cells of the organism. have the same amount of DNA and the same number of chromosomes as all other cells of the organism and develop from the same basic stem cells. contain more genetic material than less specialized cells of the same organismarrow_forwardwhat are the chances two people heterozygous for achondroplasia could have a normal child? alternate forms of a gene is called which molecules are required for translationarrow_forwardA classical experiment studying the fate determination of stem cells in the developing embryo uses the transplantation of somites from one organism to another. In such an experiment, a scientist transplanted somites 20, 21, and 22 from the right side of the neural tube from five-day-old developing quail embryos into chick embryos. The transplantation was performed in two orientations so that the order of the somites was sometimes reversed. Use the passage to answer the question. Central self-tolerance in the immune system arises when maturing T cells in the thymus undergo apoptosis when they bind to self-antigens. Based on this information, what would MOST likely occur as the chick immune system develops? A. T cells would recognize transplanted quail somites as foreign and rapidly divide. B. T cells would recognize transplanted quail somites as foreign and undergo apoptosis. C. T cells would recognize transplanted quail somites as self and rapidly divide.…arrow_forward
- why does a high concentration of Abscisic acid (ABA) inhibit elongation of the coleoptile segments?arrow_forward) Describe the action of the lysosomes in various “unique” situations, such as the destruction of specific cells during embryonic development, or the part they play in the shedding of the endometrium of the uterus during the menstrual cycle.arrow_forwardDo you think cadherins or integrins are responsible for the dependence of mammary cells on the extracellular matrix for their ability to produce milk proteins? Why?arrow_forward
- A classical experiment studying the fate determination of stem cells in the developing embryo uses the transplantation of somites from one organism to another. In such an experiment, a scientist transplanted somites 20, 21, and 22 from the right side of the neural tube from five-day-old developing quail embryos into chick embryos. The transplantation was performed in two orientations so that the order of the somites was sometimes reversed. Use the passage to answer the question. Observations of the developing chick embryo reveal that skeletal muscles develop from the transplanted somites even though motor neurons innervating those muscles arise from chick neural crest cells. Based on these observations, what is MOST likely true? A. Neural crest cells differentiate into somites. B. Neural crest cells fuse with developing somite cells. C. Neural crest cells develop from migrating somite cells. D. Neural crest cells send projections into developing…arrow_forwardLabel the stages of somatic embryogenesis shown in attachmentarrow_forwardUsing Next Generation Sequencing technology, biopsy of an embryo produced the following chromosomal sequencing results. What are the abnormality and sex of this embryo? Will this embryo produce a healthy livebirth and why?arrow_forward
- Biology: The Unity and Diversity of Life (MindTap...BiologyISBN:9781305073951Author:Cecie Starr, Ralph Taggart, Christine Evers, Lisa StarrPublisher:Cengage LearningAnatomy & PhysiologyBiologyISBN:9781938168130Author:Kelly A. Young, James A. Wise, Peter DeSaix, Dean H. Kruse, Brandon Poe, Eddie Johnson, Jody E. Johnson, Oksana Korol, J. Gordon Betts, Mark WomblePublisher:OpenStax College
- Human Physiology: From Cells to Systems (MindTap ...BiologyISBN:9781285866932Author:Lauralee SherwoodPublisher:Cengage Learning