PCl5 is commonly used to convert alcohols to alkyl halides through a substitution reaction.

An acid chloride is used to convert an amine to an amide through acylation.

Gas exchange occurs in the alveoli, where oxygen is absorbed into the blood and carbon dioxide is released from the blood.

James Watson and Francis Crick are credited with the discovery of the double helix structure of DNA.

James Watson, along with Francis Crick, is credited with the discovery of the double helix structure of DNA.

James Watson and Francis Crick are credited with the discovery of the double helix structure of DNA.

Jean-Baptiste Lamarck is known for proposing the theory of inheritance of acquired characteristics, which suggests that traits acquired during an organism's lifetime can be passed to offspring.

Stephen Jay Gould, along with Niles Eldredge, proposed the theory of punctuated equilibrium, which suggests that species remain relatively stable for long periods and then undergo rapid changes.

Solids have a definite shape and volume due to their closely packed particles.

Solids generally have the highest density due to closely packed particles.

Plasma has the highest kinetic energy as it consists of ionized particles moving freely.

Tendons are the structures that connect muscles to bones, facilitating movement.

Tendons are the structures that connect muscles to bones, enabling movement.

The fallopian tubes connect the ovaries to the uterus and are the site where fertilization typically occurs.

The ovary develops into a seed after fertilization, containing the ovules that become seeds.

Root hairs increase the surface area for water absorption from the soil.

The ovaries are responsible for the production of eggs (ova) in the female reproductive system.

The ovaries are responsible for the release of eggs during the menstrual cycle.

The ovary contains the ovules, which develop into seeds after fertilization.

The anther is the structure in the flower that contains the pollen grains.

The ovary develops into seeds after fertilization.

The ovary contains ovules, which develop into seeds after fertilization.

Stomata are small openings on the leaf surface that allow for gas exchange, including the intake of carbon dioxide and the release of oxygen.

The axon hillock is the part of the neuron where action potentials are generated.

The axon is the part of the neuron that transmits electrical impulses away from the cell body.

The axon is the part of the neuron that transmits impulses away from the cell body.

The axon is responsible for transmitting impulses away from the cell body to other neurons.

Roots are primarily responsible for the uptake of water and minerals from the soil.

Guard cells surround the stomata and control their opening and closing, regulating gas exchange and transpiration.

All of the above structures (villi, microvilli, and plicae circulares) increase the surface area for absorption in the small intestine.