#Question id: 7764
#I Life Science/ Life Sciences Group – I-V
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.
#Question id: 4965
#SCPH06 I Botany
What is thought to be the correct sequence of these events, from earliest to most recent, in the evolution of life on Earth?
1. origin of mitochondria
2. origin of multicellular eukaryotes
3. origin of chloroplasts
4. origin of cyanobacteria
5. origin of fungal-plant symbioses
#Question id: 10576
#SCPH28 | Zoology
#Question id: 2258
#SCPH01 Biochemistry
The arrangement of microtubules in eukaryotic flagella is referred to as
#Question id: 11420
#SCPH06 I Botany
We can represent the relationship of species richness to area with the equation
Where S = number of species, and c and z are both constants
Which of the following is not a logical explanation to relationship of species richness to area?