Biology Test 157

After fertilization ovule develops into seed and ovary into fruit.

After fertilization, each ovule develops into a seed. Each seed contains a tiny, undeveloped plant called the embryo. The ovary surrounding the ovules develops into a fruit that contains one or more seeds.

Hence, the correct option is (A).

Climate change may have an impact on the following agriculture, natural terrestrial ecosystems and water resources, air quality, oceans, arid coastal zones and energy and human health.

Climate change is a serious problem in the 21st century. Increased temperature resulting from increase in concentration of greenhouse gases can lead to melting of ice and rise in sea levels which may in turn impact coastal areas and some of them may get submerged. Climate change may also lead to changes in cropping pattern and agriculture in general, natural terrestrial systems and water resources. Polluted atmosphere can have a negative impact on human health.

Hence, the correct option is (D).

The cell wall of fungi is made up of chintin substance.

The cell wall is a tough, rigid layer that surrounds some types of cells. The cell wall is a characteristic feature of cells of plants, bacteria, fungi, algae, and some archaea. It is located outside the cell membrane. Cell wall composition varies from species to species and also depends on the developing stage of the organism. Protozoans and animals do not have a cell wall. In fungi, cell walls are made of chitin.

Hence, the correct option is (B).

Mendel carried out his experiment on pea plant. He focused on shape of seed and colour of seed traits.

Mendel started his first experiment on pea plants. During his attempt to study the inheritance he considered the colour and shape of the seed. He concluded from his experiment that more than one trait can be inherited from the parent plant and transmitted further. His pea plant demonstration became the foundation of the study of Mendelian traits. 

Hence, the correct option is (C).

Seeds are called products of sexual reproduction because they are formed by fusion of pollen tubes.

Seeds are called products of sexual reproduction because they are formed only after the fusion of male and female gametes. This process is called fertilization, where one of the male gametes that have entered the ovule through an opening called micropyle, fertilizes the egg cell (female gamete). The resulting zygote forms the embryo, which develops within the ovule which becomes a seed.

Hence, the correct option is (B).

In transgenics, the expression of transgene in target tissue is determined by reporter.

In a transgenic organism, reporter genes are used to determine whether a particular DNA construct has been successfully introduced into a cell, organ or tissue. Whereas promoter is the region of DNA that initiates the DNA transcription, an enhancer is the sequence of DNA that enhances the transcription when binds to the specific proteic and transgene is the gene that taken from the genome of one organism and introduces into the genome of another organism. 

Hence, the correct option is (C).

An aphid has two modes of reproduction, sexual, when food is sufficient and parthenogenesis, when there is scarcity of food and uncrowded.

Aphids thrive on the basis of their number. Their technique to survive a predator is by outnumbering them. Thus, Aphids are good at reproduction, both sexual and asexual. They reproduce by sexual methods when the food is available. The Asexual method is called, parthenogenesis, which occurs when there is a scarcity of the food. With a few exceptions, all aphids are females in spring and summer, that expand exponentially. 

Hence, the correct option is (C).

Agamogenesis is a form of reproduction that does not involve a male gamete.

Agamogenesis is the term used for the type of reproduction that does not involve a male gamete. Parthenogenesis is a type of agamogenesis. One of the most striking examples of parthenogenesis is the formation of the male honeybee. The queen honeybee produces a lot of eggs. The ones that are fertilized become female bees but the unfertilized ones develop into male worker bees known as drones. Parthenogenesis is also seen in turkey.

Hence, the correct option is (D).

The correct statements are 1, 2 and 3.

India is the largest growing economy of the world. It contributes more than 4% of the global greenhouse gas emissions and has a per capita emissions figure of approximately 1.7 metric tonnes as against a global average of about 5 metric tonnes. India's forest cover has increased over the past few years and comprises more than 20% of the total area of the country.

Hence, the correct option is (A).

Hepatic portal vein carries glucose from the digestive tract to the liver.

Hepatic portal vein carries nutrients, glucose and oxygen from the digestive tract to the liver. The liver regulates the blood glucose level before it is drained out in the systemic circulation.

Hence, the correct option is (C).