The primary function of the alveoli is gas exchange, where oxygen is absorbed into the blood and carbon dioxide is released.

The anther is the part of the stamen that produces and contains pollen grains.

The cell membrane regulates what enters and exits the cell, maintaining homeostasis.

The cell wall provides protection and support to the cell, maintaining its shape and preventing excessive water uptake.

The circulatory system is responsible for transporting nutrients, oxygen, and waste products throughout the body.

The primary function of the contraceptive pill is to prevent ovulation, thereby reducing the chances of pregnancy.

The CPU (Central Processing Unit) is responsible for processing instructions and executing commands in a computer system.

The primary function of the CPU (Central Processing Unit) is to process instructions.

The primary function of the digestive system is to break down food and absorb nutrients, making option 1 the correct answer.

The primary function of the Election Commission of India is to conduct free and fair elections in the country.

The primary function of the esophagus is to transport food from the mouth to the stomach.

Petals are primarily designed to attract pollinators with their color and fragrance.

The G2 phase is primarily for preparing the cell for mitosis, including the synthesis of proteins necessary for cell division.

The genetic code determines the sequence of amino acids in proteins, thus influencing their structure and function.

The Golgi apparatus modifies, sorts, and packages proteins for secretion or delivery to other organelles.

Aldosterone helps regulate blood pressure by controlling sodium and water balance in the kidneys.

Cortisol is a steroid hormone that helps control the body's stress response and regulates metabolism, immune response, and blood sugar levels.

Oxytocin is primarily responsible for stimulating uterine contractions during childbirth.

The primary function of the immune system is to protect the body against diseases and infections.

The integumentary system, which includes the skin, hair, and nails, serves to protect the body, regulate temperature, and provide sensory information.

The lymphatic system is responsible for transporting lymph, a fluid that contains infection-fighting white blood cells, and plays a crucial role in the immune system.

The primary function of the male reproductive system is the production of sperm, which is essential for fertilization.

Mitochondria are known as the powerhouse of the cell, where cellular respiration occurs to produce ATP.

The myelin sheath acts as an insulator and increases the speed of nerve impulse transmission through saltatory conduction.

The pancreas produces digestive enzymes that help in the digestion of carbohydrates, proteins, and fats.

Phloem is responsible for the transport of food (sugars) produced during photosynthesis from leaves to other parts of the plant.

The placenta provides oxygen and nutrients to the developing fetus and removes waste products.

The renal pelvis collects urine from the collecting ducts and transports it to the ureter.

The primary function of the respiratory system is to exchange gases, specifically to take in oxygen and expel carbon dioxide.

Ribosomes are the cellular structures responsible for synthesizing proteins by translating messenger RNA (mRNA).