Zoology MCQs for NEET — Practice Questions with Answers

Animals exhibit locomotion for various reasons, including finding shelter, searching for food, escaping from predators, and finding a mate for reproduction. Therefore, the main aims of locomotion in animals include all the options listed: shelter, search of food, escape from enemies, predation, and reproduction.

The types of movement in organisms generally include amoeboid movement, ciliary movement, and muscular movement. The 'joining process' is not a recognized type of movement in biological contexts.

Amoeboid movement is a type of movement exhibited by various cells such as Amoeba, leucocytes (white blood cells), and macrophages. These cells move using pseudopodia, which are temporary projections of the cell.

Ciliary movement can be observed in multiple parts of the body including the trachea, oviduct, and vasa efferentia. Cilia are hair-like structures that beat in a coordinated manner to move substances or cells.

Muscle tissue originates from the mesoderm, which is one of the three primary germ layers formed during embryonic development. The mesoderm gives rise to muscles, the circulatory system, bones, and other structures. For NEET students, it's important to remember that the mesoderm is responsible for forming most of the body's connective tissues, including muscles.

In an adult human, muscle tissue makes up approximately 40 - 50% of the total body weight. This high percentage is due to the extensive presence of skeletal muscles, which are essential for movement and stability. NEET students should note that this range can vary slightly based on factors such as age, sex, and overall physical fitness.

The three main types of muscles present in organisms are striated muscle, visceral muscle, and cardiac muscle. Striated muscles, also known as skeletal muscles, are responsible for voluntary movements. Visceral muscles, also referred to as smooth muscles, are found in internal organs and are responsible for involuntary movements. Cardiac muscle is found only in the heart and is responsible for pumping blood. NEET students should remember these three types as they encompass all muscle types in the human body.

Cardiac muscle contains all the mentioned bands: Intercalated discs, A-bands, and I-bands. Intercalated discs are unique to cardiac muscle and allow for synchronized contraction. A-bands are the dark bands, and I-bands are the light bands in the striated muscle structure. Therefore, the correct answer is 'All 1.2.3'.

In muscle physiology, the isotropic band (I-band) and the anisotropic band (A-band) refer to regions within the sarcomere. The I-band contains only thin filaments and appears lighter under a microscope, while the A-band contains the entire length of the thick filaments and appears darker. Thus, the correct answer is 'I - band, A - band'.

The M-line is located in the center of the H region within the sarcomere. The M-line serves as the attachment site for the thick filaments and helps maintain their alignment. Therefore, the correct answer is 'M- line'.