Excretory Products and their Elimination — BIOLOGY STD 11 Science — Question

Mention the four basic requirements for chemiosmosis to occur.

Explain heart sounds.

The plant cell cytoplasm is surrounded by both cell wall and cell membrane. The specificity of transport of substances are mostly across the cell membrane, because _________________.

Answer briefly: How does pepsinogen change into its active form?

What is the significance of splitting of water, during photosynthesis?

Give four differentiating characteristics of algae.

Lalit, student of class XI always likes to have junk food. His mother insists him to have fibre rich fruits and vegetables, because they are good for health. Lalit always ignored his mother's advise. One day, while his biology teacher was teaching about the digestive system and mechanism of digestion. She also explained about the food one should eat (Le., balanced diet) Lalit remembered his mother's advice and asked his teacher about the importance of fibre rich food in one's diet.

1. According to you, what is the advantage of having fibrous material in our food?
2. Name the term used to describe fibrous materials which is indigestible in nature.
3. Name any four fibre rich fruits.
4. What values are reflected through Lalit's character?

Trypsin acts at an alkaline pH. What provides this alkalinity? Give the two actions of trypsin.

In Opuntia the stem is modified into a flattened green structure to perform the function of leaves (i.e., photosynthesis). Cite two other examples of modifications of plant parts for the purpose of photosynthesis.