Test: Zoology Mock Test - 5 - NEET MCQ

Locomotion (performed by limbs) in humans depends on the movements of muscle fibres. Skeletal muscles are attached to the bones by tendons and help in the movement of the parts of skeleton. These muscles are under the control of conscious mind and are called voluntary muscles. Under the microscope, these muscles show transverse stripes and hence are designated as striated muscles.

(b) Innate immunity refers to nonspecific defense mechanisms that come into play immediately or within hours of an antigen’s appearance in the body. Four barriers are physical, physiological, cellular and cytokine barriers.

(II) Exopthalmic goitre is a form of hyperthyroidism.

The part of the human brain concerned with the regulation of body temperature is the Hypothalamus. Here's a brief breakdown of why:

- The hypothalamus is a small region located at the base of the brain.
- It plays a crucial role in maintaining the body's internal balance, including regulating body temperature.
- The hypothalamus receives temperature information from the body and helps to adjust it by triggering responses like sweating or shivering.
- This control is essential for maintaining a stable internal environment despite external temperature changes.

Evolutionary biologists believe that the ‘success’ of mammals is largely due to their ability to maintain a constant body temperature We maintain a constant body temperature of 37°C. In summer, when outside temperature is more than our body temperature, we sweat profusely. The resulting evaporative cooling, similar to what happens with a desert cooler in operation, brings down the body temperature. In winter when the temperature is much lower than 37°C, we start to shiver, a kind of exercise which produces heat and raises the body temperature.

Tendons, which attach skeletal muscles to bones and ligaments which attach one bone to another are examples of this tissue.

Progesterone stimulates proliferation of endometrium of uterus and prepares it for implantation of blastocysts.

Darwin finches are a good example of adaptive radiation. Adaptive radiation is a process of volution of different species in a given geographical area starting from a point and radiating to other areas of geography.

The mature spermatozoa are released from the protective sertoli cells into the lumen of the sem in ifero u s tu b u le and a p ro cess called spermiation then takes place, which removes the remaining unnecessary cytoplasm and organelles.

Archaebacteria are found in most harsh habitats. Their cell wall is adapted to tolerate extreme conditions (wall contains protein and non-cellulosic polysaccharides). Cell membranes are characterized by the presence of branched chain lipids that make them highly resistent to heat and low pH.

The correct answer is: (c) 
- High salt concentration, low water concentration.
The tissues surrounding the loop of Henle play a crucial role in the concentration of urine in the kidney.
- High salt concentration in the tissues aids in the reabsorption of water from the filtrate, maintaining a concentrated urine output.
- Low water concentration in the tissues allows for the osmotic gradient necessary for water reabsorption.
This concentration gradient is essential for the kidney's ability to regulate water balance effectively.

Species may be defined as the uniform interbreeding population of individuals which freely interbreed among themselves. Niche represents the habitat and functions of a species. Habitat is a specific place where an organisms lives.

 For example, whales, bats, cheetahs and human (all mammals) share similarities in the pattern of bones of forelimbs.

Placental mammals in Australia also exhibit adaptive radiation in evolving into varieties of such placental mammals each of which appears to be ‘similar’ to a corresponding marsupial.

Ejaculation of human male contains about 200 - 300 million sperms, of which for normal fertility 60 % sperms must have normal shape and size and at least 40 % must show energetic motility.

In biology, antrum is a general term for a cavity or chamber, which may have specific meaning in reference to certain organs or sites in the body Tertiary follicle of ovary contains a fluid filled cavity called antrum and a secondary oocyte ready for ovulation.

Aldosterone is the correct answer.

- Aldosterone is a mineralocorticoid hormone.
- It is produced by the adrenal glands.
- Aldosterone helps regulate electrolyte balance in the body, particularly sodium and potassium.
- By acting on the kidneys, aldosterone promotes the reabsorption of sodium and the excretion of potassium.
- This process helps in maintaining blood pressure and overall fluid balance in the body.

Squamous epithelium is formed of thin discoidal and polygonal cells that fit like tiles in a floor, so is also called pavement epithelium. It is found in the walls of blood vessels, in the alveoli of lung for exchange of gases, and in Bowman’s capsule of nephron for ultra filtration.

Chrysophytes include diatoms and desmids. The body of diatoms is covered by a transparent siliceous shell (silica deposited in cell wall) known as frustule.
The frustule is made of two valves, epitheca and hypotheca, which fit together like a soap box.

When an impulse (action potential) arrives at the axon terminal, it stimulates the movement of the synaptic vesicles towards the membrane where they fuse with the plasma membrane and release their neurotransmitters in the synaptic cleft

In a cockroach, wings are absent from the Prothorax. This is because:

- The Prothorax is the foremost segment of the thorax.
- It lacks wings but has certain structures like the pronotum.
- The Mesothorax and Metathorax segments bear the wings in cockroaches.
- Wings are crucial for flight and are typically located on the second and third thoracic segments in insects like cockroaches.

Curd is more nutritious than milk as it contains a number of organic acids and vitamins including B12. LAB present in curd also checks growth of disease causing microbes in stomach and other parts of digestive tract.

During pregnancy corpus luteum persists up-to the middle of pregnancy. Corpus luteum is a hormone secreting structure that develops in an ovary after an ovum has been discharged in a process called ovulation.

Sarcomere is part of myofibril between two successive Z-lines, which consists of two l-band halves, and an A-band between them.

Blue green algae (cyanobacteria) are members of kingdom monera.

The sexual cycle involves the following three steps:
(i) Fusion of protoplasms between two motile or non-motile gametes called plasmogamy.
(ii) Fusion of two nuclei called karyogamy.
(iii) Meiosis in zygote resulting in haploid spores.

Thorn of Bougainvillea and tendrils of Cucurbita are the examples of homologous organ. Homologous organs are those organs which are similar in their morphology, anatomy and embryology but dissimilar in their functions

TSH stands for Thyroid Stimulating Hormone. Here's the detailed explanation:

- Thyroid Stimulating Hormone (TSH) is produced by the pituitary gland.
- It stimulates the thyroid gland to produce hormones like thyroxine (T4) and triiodothyronine (T3).
- TSH plays a crucial role in regulating metabolism, energy levels, and growth.
- Monitoring TSH levels is essential in diagnosing thyroid disorders like hypothyroidism and hyperthyroidism.
- In summary, TSH is a key hormone that influences the functioning of the thyroid gland and overall metabolism.

(b) Family planning helps in maintaining reproductive health.