A mutation affects the function of the Hox genes in a developing Drosophila embryo. Which of the following is the MOST likely consequence?
Premature termination of embryonic development.
Failure of gastrulation.
Homeotic transformations, leading to segments developing with characteristics of other segments.
Lack of differentiation of germ layers.
Related Questions
S-shaped or sigmoid growth curve have
I. lag phase
II. log phase
III. stationary phase
IV. diminishing growth phase
Select the correct option
All except IV
All except III
All except II
I, II, III and IV
Which of the following exhibits the least plasticity?
Glass
Copper
Steel
Gold
The cells proximal (just next away from the tip) to the meristematic zone represents the phase of
Division
Maturation
Elongation
Meristematic division
Which of the following statements are correct?
I. A multicellular organism is composed of mainly three types of cells
II. Undifferentiated cells are stem cells and are unspecialised cells, which usually possesses the power of division
III. Differentiated cells are post-mitotic cells and are specialised to perform specific functions
IV. Dedifferentiated cells are differentiated cells which revert to undifferentiated state to take over the function of division
I and II
II and III
I, II and III
II, III and IV
Which extraembryonic membrane in mammals is involved in the formation of the placenta?
Amnion
Yolk sac
Allantois
Chorion
During tissue culture, if parenchyma cells from a potato tuber are used to generate callus, what process are the cells undergoing?
Redifferentiation
Transdifferentiation
Dedifferentiation
Cell elongation
Plasticity is less pronounced in which of these crop plants?
Rice
Wheat
Soybean
Maize
Richmond-Lang effect is concerned with
Promoting flowering by gibberellins
Apical dominance by auxin
Delay of senescence in leaves by cytokinin
Bolting in cabbages by ethylene
During oogenesis in mammals, polar bodies are formed. Which statement best describes the function of polar bodies?
To provide nutrients to the developing oocyte.
To allow for the reduction of chromosome number while retaining most of the cytoplasm in the oocyte.
To initiate the process of fertilization.
To guide the sperm towards the oocyte.
A scientist is culturing leaf mesophyll cells. The cells lose their specialized features and form an unorganized mass. This is NOT an example of:
Dedifferentiation
Callus formation
Cellular totipotency
Differentiation
