Explanation

Nitrogen fixation refers to the process of converting atmospheric nitrogen (N2) into a usable form for plants.

This can happen through several methods: 

Atmospheric fixation:

• This occurs naturally when lightning strikes, breaking the strong nitrogen-nitrogen triple bond and creating nitrogen oxides that can dissolve in rainwater.

Industrial fixation:

• This involves using high-temperature and pressure processes, like the Haber-Bosch process, to convert nitrogen into ammonia.
• This method is crucial for industrial agriculture. 

Biological fixation:

• This process is carried out by certain bacteria, such as those found in the root nodules of legumes (like peas and beans), or free-living bacteria in the soil.
• These bacteria can break down the nitrogen molecule and convert it into ammonia or other usable nitrogen compounds. 

Explanation

The breakdown of two molecules of glucose in aerobic respiration will produce 12 molecules of carbon dioxide (CO2). 

The balanced chemical equation for aerobic respiration shows that one molecule of glucose (C6H12O6) produces six molecules of carbon dioxide (6CO2).

Therefore, if two molecules of glucose are broken down, the total number of CO2 molecules produced will be:

2 molecules of glucose * 6 molecules of CO2 per glucose = 12 molecules of CO2. 

Explanation

The pectoral girdle consists of the clavicle (collarbone) and the scapula (shoulder blade).

The sternum is part of the axial skeleton, the pelvic bone is part of the pelvic girdle, and the hyoid bone is in the neck. 

Explanation

 One gram atom of any element refers to one mole of its atoms.

- The molar mass of chlorine (Cl) is approximately 35.5 g, so:

  - One gram atom of chlorine = 1 mole of Cl atoms = 35.5 g, not 71 g (which is for Cl₂ molecules).

Explanation

Resistivity after cutting a wire in half:

Resistivity 𝜌 is a material property, independent of shape, size, or length.

When a wire is cut, resistance changes, but resistivity remains the same.

Explanation

The Van der Waals constant "a" represents the magnitude of intermolecular attractions.

A higher "a" value means stronger intermolecular forces.

- He and H₂ are very light, nonpolar, and have weak intermolecular forces.

- N₂ is also nonpolar but heavier than He and H₂.

- CH₄ (Methane) is nonpolar but larger and more polarizable, so it has stronger London dispersion forces.

→ Therefore, CH₄ has the highest "a" value among the given options. 

Explanation

Explanation

Epinephrine (adrenaline) is used as a bronchodilator to treat asthma

They as a heart stimulant in emergencies, such as during cardiac arrest.

Explanation

Human placental lactogen and leutotrophic is a hormone responsible for lactation

Human placental lactogen (hPL) is a hormone released by the placenta during pregnancy.

Leutotrophic hormone stimulates the growth of the milk gland and secures milk only after delivery of the fetus plus the placenta. 

It gives nutrition to the fetus.

It also stimulates milk glands in the breasts for breastfeeding.

Additional information:

Lactation is the process of producing and releasing milk from the mammary glands in your breasts.

It begins in pregnancy when hormonal changes signal the mammary glands to make milk in preparation for the birth of your baby.

Explanation

Abyssal hills form in the young oceanic lithosphere near mid-ocean ridges. 

They are the most abundant geomorphic structures on Earth

They cover more than 30% of the ocean floor.

The greatest abundance of abyssal hills occurs on the floor of the Pacific Ocean.