Answer:
The C. elegans embryo is a powerful model system for studying the mechanics of metazoan cell division. Its primary advantage is that the architecture of the syncytial gonad makes it possible to use RNAi to generate oocytes whose cytoplasm is reproducibly (typically >95%) depleted of targeted essential gene products via a process that does not depend exclusively on intrinsic protein turnover. The depleted oocytes can then be analyzed as they attempt their first mitotic division following fertilization. Here we outline the characteristics that contribute to the usefulness of the C. elegans embryo for cell division studies. We provide a timeline for the first embryonic mitosis and highlight some of its key features. We also summarize some of the recent discoveries made using this system, particularly in the areas of nuclear envelope assembly/ dissassembly, centrosome dynamics, formation of the mitotic spindle, kinetochore assembly, chromosome segregation, and cytokinesis.
1. The C. elegans embryo as a system to study cell division
The C. elegans embryo is a powerful model system for studying the mechanics of metazoan cell division. Its primary advantage is that the syncytial gonad makes it possible to use RNA interference (RNAi) to generate oocytes whose cytoplasm is reproducibly (>95%) depleted of targeted essential gene products. Introduction of dsRNA rapidly catalyzes the destruction of the corresponding mRNA in many different systems. However, depletion of pre-existing protein is generally a slow process that depends on the half-life of the targeted protein. In contrast, in the C. elegans gonad, the protein present when the dsRNA is introduced is depleted by the continual packaging of maternal cytoplasm into oocytes (Figure 1). Since depletion relies on the rate of embryo production instead of protein half-life, the kinetics tend to be similar for different targets. By 36-48 hours after introduction of the dsRNA, newly formed oocytes are typically >95% depleted of the target protein.
Explanation:
Answer:
subliminal perception.
Explanation:
Subliminal perceptions, also known as subliminal messages, are messages, either visual or auditory, that are presented just beyond the threshold of human perception. A subliminal perception may not be audible enough that the conscious mind might register it but be audible enough for the subconscious mind.
For example it might be an image transmitted briefly and unperceived consciously and yet perceived unconsciously.
Answer: There re two different types of phenotypes in the offsprings that is Round yellow and Round green.
Explanation-
As per the Mendelian inheritance, Round shape and yellow color of pea are dominant over wrinkled shape and green color of pea.
According to the question, genotypes of parents are- RrYy ( heterzygous for round and yellow) and RRYy ( homozygous for round and heterozygous for yellow).
The first parent can produce four different gametes that is RY, Ry, rY, ry whereas the second parent will produce only two types of gametes that is RY and Ry.
When they are crossed, they will produce two different phenotypes in the offsprings.
Refer punnett square.
Answer:
Bone marrow.
Explanation:
Hematopiesis may be defined as the formation of the blood cells by the precursor stem cells. This process occurs in the bone marrow, thymus and liver.
The red blood cells are enucleated cells with the minimum span of around 120 days. These cells are processed and destroyed in the spleen. The iron is recovered from the red blood cells and sent again into the bone marrow for the production of new blood cells.
Thus, the answer is bone marrow.