Lactase refers to an enzyme that can dissociate lactose sugar into glucose and galactose. This enzyme plays an important role in the digestion of milk that comprises high lactose sugar. In case, if a mutation occurs in the gene codon of lactase, then two possibilities can take place. These are as follows:
1. Loss of mutation: In this case, the person becomes lactose intolerant because of mutation in lactase gene codon. Due to this, there is low mRNA expression and thus low production of the enzyme lactase. This is also known as lactase non-persistent phenotype.
2. Gain in mutation: In this case, the person gain an increase in mRNA expression of the lactase gene, thus more production of lactase takes place than usual. This kind of individual exhibits lactase persistent phenotype.
Answer:
Granulosa cells
Explanation:
Foliculogenesis is a dynamic and complex process through which the follicle goes through many stages of development in a short period (approximately 60 days in humans and some chimpanzees).
The stages classification is based on morphological changes such as follicular size or diameter, the number of follicular cell layers, etcetera. These classifications might vary among authors but could be denominated as:
- De Graaf follicles (This is the one shown in the image)
Through each stage, there are certain modifications in the oocyte, follicular cells, and connective tissue. As the oocyte grows, the follicular cells might reach a size twice or three times bigger than the ones of the primordial follicles. Their shape also changes and they adopt an aspect of stratified epithelium. Their cytoplasm gets a granulous aspect, after what these cells receive the name of <u><em>granulous cells</em></u>. The De Graaf follicle characterizes for having a space named follicular antro that displaces the oocyte to one of the sides.
The oocyte at this point gets surrounded by <u>zona pellucida</u> and <u>corona radiata </u>.
The follicular antro (The highlighted structure) separates the oocyte from the externally located <u>granulosa cells</u> or follicular cells.
The correct answer is option (C) Gray rabbits would be eliminated by predators.
Camouflage is an adaptation by organisms allowing them to blend with the environment. This helps them in surviving or escaping from their predators. It can be throught coloration or developing a particular pattern or mimicry.
The example given above is a type of camouflage through concealing coloration. Concealing coloration includes having a fixed camouflage and changing the camouflage depending on the environment. Grey rabbits cannot exhibit camouflage as the backgroud is dark rocks and light stones. As a result, these rabbits are clearly visible to the predators and get elimiated by them.
Answer:
The correct answer is c. production of white blood cells, red blood cells, and platelets.
Explanation:
Hematopoiesis is the formation of all types of blood cellular components and components of plasma like white blood cells, red blood cells, and platelets by hematopoietic system which involves the bone marrow, liver, and spleen.
First, the hemopoietic stem cell divides into common myeloid progenitor and common lymphoid progenitor. From myeloid progenitor RBC, platelets, basophils, eosinophils, neutrophils, and macrophages are formed.
Common lymphoid progenitor gives rise to T- lymphocytes, B- lymphocytes, and natural killer cells. Therefore the correct answer is c. production of white blood cells, red blood cells, and platelets.