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TLS Online TPP Program

#Question id: 34143

Which of the following best explains how normal plasma oxytocin levels at the onset of labor can still result in powerful uterine contractions?

#Unit 7. System Physiology – Animal
  1. The uterus begins secreting its own oxytocin, which inhibits progesterone and directly stimulates the fetal adrenal cortex.
  2. The descent of the fetus stimulates a hypothalamic feedback loop that rapidly increases systemic oxytocin to supraphysiologic levels.
  3. There is a marked upregulation of uterine oxytocin receptors at term, making the myometrium hypersensitive even to baseline oxytocin levels, initiating a positive feedback loop.
  4. Oxytocin receptors on the cervix and vagina directly stimulate the anterior pituitary to secrete oxytocin during early labor.
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TLS Online TPP Program

#Question id: 3603

#Unit 8. Inheritance Biology

Blue follower is dominant over white flower and long pollen is dominant over short pollen. A plant with Blue flower and short pollen was cross with white flower and long pollen. Their progeny, ½ had a blue flower with long pollen and another ½ had a white flower with long pollen was allowed to intercross. Which of the following observation is correct among these progeny when independently assort?
TLS Online TPP Program

#Question id: 3604

#Unit 8. Inheritance Biology

Genes A, B and C. control three phenotypes which assort independently; A plant with the genotype aaBbCc were cross with AabbCc. What is the probability for progeny which show the dominant phenotype for AT LEAST ONE of the phenotypes controlled by genes A, B and C?
TLS Online TPP Program

#Question id: 3605

#Unit 8. Inheritance Biology

Male Plant blue flower with long pollen was crossed with female plant white flower with long pollen. Analysis of progeny of this cross showed that 50% of the progeny was red with long pollen while the remaining 50% of the progeny was white with long pollen. Which one of the following statements is a possible explanation of the above results?
TLS Online TPP Program

#Question id: 3606

#Unit 8. Inheritance Biology

Genes A, B and C. control three phenotypes which assort independently; A plant with the genotype Aa Bb Cc is selfed. What is the probability for progeny which show the heterozygocity for AT LEAST ONE locus?
TLS Online TPP Program

#Question id: 3607

#Unit 8. Inheritance Biology

Cystic fibrosis is caused by a recessive lethal gene and can be detected by an excess concentration of chloride in sweat. If a sweat test reveals a man to be heterozygous and his wife to be homozygous normal, what are the chances that their children will have the disease?
TLS Online TPP Program

#Question id: 3608

#Unit 8. Inheritance Biology

Mendel crossed plants with the seed characters round and yellow with plants having the contrasting seed characters wrinkled and green. Round is dominant

to wrinkled, and yellow is dominant to green. The F1 progeny were all round and yellow. What will be genotype ratio in F2 generation?