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TLS Online TPP Program

#Question id: 11378

Which of the following set of conditions will qualify a species to be considered as critical endangered (EN) as per IUCN criteria?

#Unit 10. Ecological Principles

  1. >90% reduction in population size, <100 km2 area of occupancy, at least 50% estimated extinction risk in three generations.

  2. <2,50 individuals with declining population, <250 mature individuals, at least 20% estimated extinction risk in 20 years

  3. <250 individuals with declining population, <50 mature individuals, at least 50% estimated extinction risk in 10 years.
  4. >90% reduction in population size, <10 km² area of occupancy, at least 50% estimated extinction risk in five generations
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TLS Online TPP Program

#Question id: 7759

#Unit 5. Developmental Biology

WRKY plant-specific group of transcription factors that play important role in many plant metabolic and developmental processes such as;
a) It contain a 30 amino acid region named for the conserved amino acid sequence WRKYGQK in its N-terminal domain
b) It is an important regulators of plant–pathogen interactions as well as senescence
c) WRKY53 is involved in the regulation of dark-induced leaf senescence
d) In Arabidopsis, leaf senescence is delayed in knockout mutants of the WRKY53 gene
e) WRKY53 also binds to the promoter of the WRKY53 gene, inhibiting its own expression in a negative feedback loop
Which of the following given prediction about WRKY transcription factor is correct?
TLS Online TPP Program

#Question id: 7761

#Unit 5. Developmental Biology

Correct sets of genes are well known to be involved in aging and its prevention, and each set appears to be conserved between phyla and even kingdoms. 
a. DNA repair enzymes
b. proteins of the insulin signaling pathway
c. proteins in the mTORC1 signaling pathway
d. chromatin remodeling enzymes
TLS Online TPP Program

#Question id: 7762

#Unit 5. Developmental Biology

Correlation between life span and the ability of fibroblasts to repair DNA in various mammalian species, Repair capacity is represented in autoradiography by the number of grains from radioactive thymidine per cell nucleus. According to graph, which factor exist on x-axis ? Note that the y-axis (life span) is logarithmic.
TLS Online TPP Program

#Question id: 7763

#Unit 5. Developmental Biology

Two major sources of mutation are radiation and reactive oxygen species (ROS).The reactive oxygen species hypothesis for aging postulates that 
1) Senescence results from the accumulation of DNA, lipid, and protein damage inflicted by ROS of mitochondrial origin; and
2) Mitochondria of long-lived species should produce high ROS than do mitochondria of short-lived species.
3) the capacity of mitochondria to consume ROS might distinguish long-lived species from short-lived species, rather than differences in ROS generation. 
TLS Online TPP Program

#Question id: 7764

#Unit 5. Developmental Biology

Cellular senescence may have evolved to protect organisms against cancer. Instead of dividing out of control, the cells die. Cellular senescence appears to be regulated by several tumor suppressor genes, especially p53.what is the most appropriate reason behind this,

1) Transcription factor p53 is thought to suppress tumorigenesis by causing cell arrest and senescence in response to short telomeres, DNA damage, and viral or external signals to divide

2) This factor can stop the cell cycle, cause cellular senescence in rapidly dividing cells, instruct genes to initiate cellular apoptosis, and activate DNA repair enzymes.

3) Induction of apoptosis or cellular senescence by p53 always beneficial.
TLS Online TPP Program

#Question id: 7765

#Unit 5. Developmental Biology

The enzyme complex or gene that maintains telomere integrity is________, which acts as an antisenescence complex. Mice and humans with its deficiencies age prematurely (Mitchell et al. 1999). Overexpressing or reactivating it in senescent cells extends longevity in mice without increasing cancer,