Name the layer of meninges which is delicate and highly vascular lying in close contact with CNS.

Which layer of meninges is tough, non-vascular and attached to inner side of cranium?

Name the outer collagenous connective tissue and inner vascular layer of the testis.

Name the supporting cells which secrete-myelin sheath around axon of CNS in man.

Name the layer which supplies nourishment is the developing pollen grains. OR Name teh layer which supplies nourishment to the developing pollen grains.

Name the following The protective layers present in the space between the delicate central nervous system and its bony covering.

It is observed thatdeficiency of a particular element showed itssymptomsinitially in older leaves and then in younger leaves. Name two elemtns which are highly mobile and two which are relatively immobile.

The coutries which do not have oil reservatirs in their land import oil from other countries. But sometimes during transporting oil through sea routes, accidental oil spilling occurs. This oil spilled in the ocean may prove fatal and toxic to aquatic animals. Therefore, removel of this spilled oil is essential for protection of aquatic life. For removing this oil layer, certain microbes like Pseudomonas spp. and Alcanivarax borkumensis are used. These microbes have the ability to destroy the pyridines and other toxic chemicals. The hydrocarbonoclastic bacteria (HCB) are able to decompose the hydrocarbons and bring about the reaction carbon with oxygen resulting in formation of CO_(2) and water. Like oil spills cause damage to aquatic life, platic forms the major part of the grabage on land. Plastics are difficult to degrade as they are made up of PET. By research, various species like Vibrio and Idenoella sakaiensis which can degred PET.By research, various species like Vibrio and Ideonella sakaiensis which can degrade PET have been identified. There are cartain species of microbes which can decompose rubber from garbage. Based on the given paragraph answer the following question. Name any two species of microbes which can degrade rubber from

Read the following paragraph and answer the following questions given below it : Construction of a compound microscope : (i) Acompound microscope consists of a metal tube fitted with two convex lenses at the two ends. These lenses are called the objective lens ( the lens directed towards the object ) and the eyepiece ( the lens directed towards the eye ). Both the lenses are small in size , but the cross section of the objective lens has a short focal length . the focal length of the eyepiece is more than that of the objective lens . (ii) The metal tube is mounted on a stand . thr principal axes of the objective lens and the eyepiece are along the same line . The distance between the object and objective lens can be changed with a screw . It is possible to change the distance between the objective lens and the eyepiece. Working : (i) The object to be observed is illuminated and placed in front of the objective lens. slightly beyond the focal length of the objective lens. it's real , inverted and enlarged image is formed by the objective lens on the other side. (ii) This intermediate image lies with in the focal length of the eyepiece. It serves as an object for the eyepiece. The eyepiece works as a simple microscope . the final image is virtual, highly enlarged and inverted with respect to the original object . It can be formed at the minimum distance of distinct vision from the eyepiece . The final image is observed by keeping the eye close to the eyepiece. Use: This microscope is used to observe blood cells , microorganisms , etc. In a compound microscope , which lens has greater focal length ?

Read the following paragraph and answer the following questions given below it : Construction of a compound microscope : (i) Acompound microscope consists of a metal tube fitted with two convex lenses at the two ends. These lenses are called the objective lens ( the lens directed towards the object ) and the eyepiece ( the lens directed towards the eye ). Both the lenses are small in size , but the cross section of the objective lens has a short focal length . the focal length of the eyepiece is more than that of the objective lens . (ii) The metal tube is mounted on a stand . thr principal axes of the objective lens and the eyepiece are along the same line . The distance between the object and objective lens can be changed with a screw . It is possible to change the distance between the objective lens and the eyepiece. Working : (i) The object to be observed is illuminated and placed in front of the objective lens. slightly beyond the focal length of the objective lens. it's real , inverted and enlarged image is formed by the objective lens on the other side. (ii) This intermediate image lies with in the focal length of the eyepiece. It serves as an object for the eyepiece. The eyepiece works as a simple microscope . the final image is virtual, highly enlarged and inverted with respect to the original object . It can be formed at the minimum distance of distinct vision from the eyepiece . The final image is observed by keeping the eye close to the eyepiece. Use: This microscope is used to observe blood cells , microorganisms , etc. State which distance is adjusted to observe the object with a compound microscope ?