FPSC Everyday Science MCQs

Ribosomes join amino acids according to genetic instructions.
They may be free in the cytoplasm or attached to rough ER.

The cell membrane is selectively permeable.
It regulates exchange between the cell and its environment.

The plant cell wall is mainly made of cellulose.
It supports the cell and helps prevent bursting.

Chloroplasts contain chlorophyll and photosynthetic machinery.
They convert light energy into chemical energy.

Diffusion is driven by random particle motion.
Net movement continues down a concentration gradient.

Osmosis is a special case of water movement across a membrane.
It affects cell volume and water balance.

Water enters the cell and enlarges the vacuole.
The cell contents press against the wall, making the cell turgid.

Tissues consist of coordinated cells with related roles.
Examples include muscle tissue and epithelial tissue.

Pencil cores are made mainly of graphite mixed with clay.
Graphite is a form of carbon.

In graphite, each carbon forms three bonds and leaves mobile electrons.
These electrons carry charge along the layers.

Diamond and graphite are allotropes of carbon.
Their different structures give very different properties.

Each carbon atom bonds strongly to four others in diamond.
The rigid network resists deformation.