SAT (Stage-1) Mock Test - 61

Metals are electropositive elements and react by loss of electrons.
Hence, they get oxidised and act as reducing agents.
More reactive metals are stronger reducing agents.
K > Na > Cu > Ag
This is the decreasing order of the reactivity as well as reducing power of metals.

Metals and non-metals react by the transfer of electrons and form ionic bonds.
Thus, magnesium and chlorine form an ionic bond.
Mg + Cl₂ → MgCl₂
Reaction mechanism:
Mg → Mg⁺² + 2e^-
2Cl + 2e^- → 2Cl^-
Mg⁺² + 2Cl^- → MgCl₂

Number of electrons in 1 molecule of CH₄ = 6 from C - atom + 4 from H - atoms = 10
Number of electrons in 1 mole of CH₄ = 10 × 6.022 × 10²³ = 6.022 × 10²⁴

Heredity is the passing of traits from parents to their offspring, either through asexual reproduction or sexual reproduction. This is the process by which an offspring cell or organism acquires or becomes predisposed to the characteristics of its parent cell or organism.

Complete breakdown of glucose occurs in two steps. First is glycolysis. In this, glucose is broken down into pyruvate. This occurs in cytoplasm. Pyruvate then enters mitochondria, which is the site of Kreb's cycle. The complete oxidation of pyruvate occurs here, leading to the formation of carbon dioxide and water.

The intestinal microflora is a complex ecosystem containing over 400 bacterial species. These bacteria can synthesise vitamins B and K.

Phenotypic ratio of F₂ monohybrid cross is 3 : 1.
A cross of two F₁ hybrids, heterozygous for a single trait, that displays incomplete dominance is predicted to give a 1 : 2 : 1 ratio.
A dihybrid cross shows a phenotypic ratio of 9 : 3 : 3 : 1 in the F₂ generation.
A monohybrid test cross of heterozygous dominant with pure recessive gives a 1 : 1 phenotypic ratio.

The correct hierarchy of complexity of organisms is in option (3).

Organism → Population → Community → Ecosystem → Biosphere

In lizards, eggs at high temperature develop into male progeny, while eggs at low temperature develop into female progeny.

According to the theory of evolution by Charles Darwin, formation of a new species is generally due to accumulation of variations over several generations.

The gametes of a plant of genotype RrYy should have the genotypes RY, Ry, rY and ry.

If small amount of carbon monoxide is inhaled, it displaces oxygen from oxyhaemoglobin and results in formation of carboxyhaemoglobin, which does not act as oxygen carrier. Thus, it may even lead to death.

Birds in a tree ecosystem can be omnivores. Hence, occupy trophic level 3. Similarly frogs in a grassland ecosystem occupy trophic level 3.

The liver is an abdominal glandular organ in the digestive system. It is located in the right upper quadrant of the abdomen, under the diaphragm.

People who eat fat rich diet tend to have elevated cholesterol level. A high cholesterol can be dangerous as it tends to block arteries and cause high blood pressure.