Hypomorphic alleles of a pleiotropic gene essential for early development can sometimes provide enough gene activity for an organism to survive early development. In such cases, the mutant
Mice homozygous for null alleles of Fgf8 (fibroblast growth factor 8) die during early embryogenesis, obscuring a later role for Fgf8 in setting up left/right asymmetry of organs. However, mice homozygous for hypomorphic Fgf8 alleles, develop much further and reveal that Fgf8 protein is a determinant of leftness. In Fgf8 mutants, many organs such as the heart are left/right reversed as shown in the following figure.
How might these Fgf8 hypomorphic mutant alleles been generated? (More than one answer is possible.)
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GENETICS(LL)-W/CONNECT >CUSTOM<
- 12. Which of the following molecules can absorb light? a. Pigments b. Chlorophyll c. Rhodopsin d. Carotenoids e. All of the abovearrow_forwardWhich of the following proteins or protein complexes is directly required for the targeting of mitochondrial inner membrane multipass proteins, such as metabolite transporters, whose signal sequence is normally not cleaved after import? OA. TIM22 OB. TIM23 C. OXA OD. Mia40 OE SAMarrow_forwardQUESTION 9 An animal cell has been wounded and has a small rupture in its plasma membrane. Which of the following is more likely to happen next? OA. The cell rapidly cleaves by cytokinesis. OB. The rate of receptor-mediati endocytosis is increased. OC. The rate of exocytosis is increased. OD. The rate of pinocytosis is increased.arrow_forward
- For the a subunit of a trimeric G protein, A. a G-protein-coupled receptor GPCR) acts as a guanine nucleotide exchange factor (GEF), whereas a regulator of G protein signaling (RGS) can act as a GTPase-activating protein (GAP). B. a GPCR acts as a GAP, whereas an RGS can act as a GEF. C. both a GPCR and an RGS can act as a GEF. O D. both a GPCR and an RGS can act as a GAP OE. None of the above.arrow_forwardA cell expresses a transmembrane protein that is cleaved at the plasma membrane to release an extracellular fragment. The fragment binds to receptor proteins on nearby cells and activates signaling pathways resulting in altered gene expression patterns in the cells. What form of intercellular signaling does this represent? OA. Contact-dependent signaling B. Paracrine signaling OC. Synaptic signaling D. Endocrine signaling E. Autocrine signalingarrow_forwardWhich of the following drive nuclearly encoded proteins import into the mitochondrial matrix? OA. ATP hydrolysis OB. Membrane Potential OC. K+ Ions OD. A and B OE. None of the abovearrow_forward
- Which of the following statements is true regarding Cholesterol import into the cell? OA. It is transported within LDL B. Receptor mediated endocytosis is involved OC. Release of cholesterol occurs in the Lysosome D. All of the above are true statements OE. None of the above are true statementsarrow_forwardIn which of the following schematic drawings of signaling pathways does the activation of the receptor lead to gene expression? Activating and inhibitory steps are indicated with (+) and (-), respectively. OA OB ㅇㅂㅇㅂㅇㅁ (+) Gene Expression Activated Signaling proteins Transcription receptor activator Bl D Gene Expression Gene Expression ㅁㅁㅇ Gene Expression Gene Expressionarrow_forwardWhich of the following events normally activates a GTP-binding protein? OA. GTP hydrolysis by the protein OB. Activation of an upstream GTPase-activating protein OC. Activation of an upstream guanine nucleotide exchange factor OD. Phosphorylation of a bound GDP molecule by an upstream phosphorylase OE. Pi release after GTP hydrolysisarrow_forward
- Proteins that are synthesized on the Rough ER are imported into the ER lumen after their signal sequence is recognized. Which of the following is responsible for the signal recognition? OA. Signal Recognition Particle, OB. Signal Sequence C. Stop-transfer sequence OD. Both B and C OE. None of the abovearrow_forwardStroma Light 4 H 4 H I Thylakoid- membran 2 H₂O D1 D2 Min Light 2,6 ATP 2 NADP+ 2 NADPH/H+ Fp 2,6 ADP +2,6 P 8 H+ 12 H+ 4 H+ Lumen PS II Cyt bef PS I ATP-Synthase 12345 5a 5b 6arrow_forwardWhich of the following statements is TRUE regarding the signal recognition particle (SRP)? OA. SRP is made up of RNA and Proteins B. SRP binds to the signal sequence OC. SRP binds to the elongation factor binding site on the ribosome and pauses translation D. All of the above are true statements OE. None of the above are true statementsarrow_forward
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