A is correct (ur welcome)
Answer:
Bat boxes at homes provide housing to insect-eating bats which has two major positive effects on the environment:
- Bat boxes provide bats a natural habitat and they act as natural pest control in the environment. They are very helpful for reducing or controlling the population of mosquito and balance the food chain in the environment.
- Bat is known as very good pollinators which helps in the pollination of flowers or spread their seeds. So bat boxes at home increase pollination in nearby areas and increase biodiversity in the environment.
Hence, bat boxes at houses have a positive effect on the environment.
There are 2 types of transport mechanisms that involve the movement of materials across the cellular membrane:
1. Passive Transport Mechanisms which is the movement of materials that does not require energy. Instead the movement relies on the permeability of the cell. Under this are three kinds of passive transport mechanisms:
a. Simple Diffusion:
- the movement of materials from a region of higher concentration to lower concentration. No external energy is necessary for the movement. The materials supply the energy themselves.
b. Facilitated Diffusion:
- This differs from simple diffusion because the movement is facilitated by proteins that make up the structure of the membrane. The proteins include channel proteins that allow ions and smaller molecules to cross the membrane. The other protein are the carrier proteins, which bind to materials like sugar molecules and move it across the membrane.
c. Osmosis:
- This is the diffusion of water across the membrane. Osmosis moves water from regions where there are more water molecules of water per volume to regions where there are less water molecules per volume.
2. Active transport on the other hand is a movement mechanism that requires energy. It uses the energy to send materials against the direction it is coming from through simple diffusion. This mechanism is used in a way to keep unwanted ions or other materials out of the cell.
The answer is spicules. These
sharp-pointed structures are formed from calcium carbonate skeleton of
the organisms. They can also be formed from silica. They can be big (megascleres),
or microscopic (microscleres). Also dependent on the number of axis on the spicules, they are classified as monoaxon,
triaxon or polyaxon.