General Science Mixed Quiz: Set 104

With constant acceleration the distance covered is s = ut + ½at², and the first term contains the initial velocity u. This is the second equation of motion.

Meiosis makes gametes that differ from one another, and fertilization joins a gamete from each of two parents, so every offspring gets a new mix of genes.

This is absolute zero, more exactly −273.15°C or 0 kelvin, the temperature below which nothing can be cooled. Temperature measures the random motion of particles.

Above the threshold, the kinetic energy of the ejected electrons rises as the frequency of the light rises, so the statement that it does not change is wrong.

All three statements correctly describe how particles move in the two kinds of mechanical waves. In a longitudinal wave, such as sound in air, the particles vibrate back and forth along the direction in which the wave travels.

The anther is the top part of the stamen, the male organ of a flower, and pollen grains form inside it.

One hertz means one complete cycle per second, so a frequency of 3 Hz means the current completes three full cycles every second.

To just complete a vertical circle, a bob on a string needs a speed of at least √(5gL) at the lowest point, and √(5 × 10 × 0.5) = √25 = 5 m/s. A string can only pull, never push.

Litmus is a purple dye extracted from certain lichens, such as species of Roccella, and it turns red in acid and blue in base.

High pressure pushes the gas molecules close together and low temperature slows them down, so the attractive forces can hold them as a liquid.

This follows the reactivity series of metals, in which zinc lies above iron, iron above lead and lead above copper.

Crown gall is caused by the bacterium Agrobacterium tumefaciens, which enters through a wound near the base, or crown, of the stem and makes the plant grow rough tumour-like swellings there.

Graphene is not a wide band-gap semiconductor; it has practically zero band gap and behaves like a semimetal.

The endodermis is the innermost layer of the cortex that surrounds the vascular tissue; it is not a part of the vascular bundle itself.

In paper making the raw plant material is cooked with caustic soda, which dissolves the gums, resins and lignin that bind the cellulose fibres together.

The spring constant is force divided by extension, so its SI unit is newton per metre. Hooke's law says that, within the elastic limit, the restoring force of a spring is proportional to how far it is stretched or compressed: F = −kx.

The cell membrane is flexible, and this lets a cell fold it around food and other material and take it in.

Both work in neutral to alkaline conditions, in the mouth and the small intestine, and stop working in the acid of the stomach.

Urea is the body's way of getting rid of the nitrogen that comes from breaking down proteins, and only proteins among these contain nitrogen.

These are the signs of scurvy, the disease caused by a lack of vitamin C (ascorbic acid). Vitamin C is needed to make collagen, the protein that holds together gums, skin, blood vessels and bone.