Biology Quiz 7

The liver secretes bile juice that does not contain enzymes but helps in digestion. Salivary gland secrets ptyalin which is the first digestive enzyme. The small intestine secrets maltase, and peptidase. The pancreas produces pancreatic amylase, trypsin, nuclease, nucleosidases, and lipase.

Rayon (also called viscose) is a semi-synthetic fiber, made from natural sources of regenerated cellulose, such as wood and related agricultural products. It has the same molecular structure as cellulose. It is also called viscose.

The hybrid between horse and donkey is called Mule. Usually, it's the male donkey (jack) mating with a female horse (mare) to produce a mule, which can come in either male or female. Due to the odd number of chromosomes, they can't reproduce.

Cirrhosis is usually a result of liver damage from conditions such as hepatitis B or C, or chronic alcohol use. Heavy metals like copper may exacerbate liver damage. The toxicity of copper can result in brain damage, liver failure, or death if it is not treated.

The best wavelengths of visible light for photosynthesis fall within the blue range (425–450 nm) and red range (600–700 nm). Therefore, the best light sources for photosynthesis should ideally emit light in the blue and red ranges. Green light is the least effective in photosynthesis.

Taste buds are small cells on the tongue that allow to recognize the flavours of food and drink. The tip of the tongue contains the 'sweet' taste buds while the 'bitter' taste buds are present in the back. Either side of the front tongue contains 'salt' taste buds while the 'sour' taste buds are present behind this.

The ability of the eye to see in the dark is due to the production of a purple pigment known as Rhodopsin. Rhodopsin, also known as visual purple, is the photopigment used by the rods and is the key to night vision. It is a pigment-containing sensory protein that converts light into an electrical signal.

There are 23 chromosomes in a human ovum and 23 chromosomes in human sperm. Healthy humans have 23 pairs of chromosomes in which 22 pairs are autosomes and 2 are sex chromosomes. The ovum (female gamete) is formed by the meiosis due to which they have only the half number of chromosomes, which means 22 autosomes (11 pairs) and 1 sex chromosome.

The average normal body temperature is generally accepted as 98.6°F (37°C).

Barr body is the inactive X-chromosome in the somatic cells of mammalian females. Human females have two X chromosomes, while males have one X and one Y. In all of the female somatic cells, which don't take part in sexual reproduction, one of the X chromosomes is active, and the other is inactivated in a process called lyonization, becoming the Barr body.