Biology: Body Systems 3

Explanation
Because crossing over occurs during meiosis and the male and female gamete each contribute half the chromosomes, the resulting offspring will have new genetic combinations from its parents.

Explanation
The ovaries produce the gametes. The other organs are secondary.

Explanation
The male gamete is called a sperm. Sperm is the reproductive cell produced by males, which is responsible for fertilizing the female gamete (egg) during sexual reproduction. Sperm cells are typically small and motile, equipped with a tail that allows them to swim towards the egg for fertilization. The testes, on the other hand, are the male reproductive organs responsible for producing sperm. While the testes are involved in the production of sperm, they are not the actual male gamete themselves.

Explanation
A human gamete, which is a sperm or an egg cell, contains 23 chromosomes. This is because gametes are haploid, meaning they have half the number of chromosomes compared to other cells in the body. In humans, the diploid number of chromosomes is 46, but during the process of meiosis, the number is halved to 23 in gametes. This allows for the combination of chromosomes from both parents during fertilization, resulting in the normal diploid number of chromosomes in offspring.

Explanation
The development of secondary sex characteristics is controlled by hormones, which are produced by the endocrine system. The endocrine system is responsible for producing and releasing hormones into the bloodstream, which then travel to target cells or organs to regulate various bodily functions, including the development of secondary sex characteristics. Sperm and zygote are not involved in the production of hormones or the development of secondary sex characteristics.

Explanation
The digestive system is responsible for breaking down food, absorbing nutrients, and eliminating waste. Filtration of the blood is not a function of the digestive system. Instead, filtration of the blood is carried out by the kidneys in the urinary system. The kidneys filter waste products from the blood and produce urine, which is then eliminated from the body.

Explanation
Before our cells can use food, it must go through the process of digestion and absorption. Digestion breaks down the food into smaller molecules that can be absorbed by the body. These molecules are then transported to the cells, where they can be used for energy, growth, and repair. Absorption occurs in the small intestine, where nutrients are taken up by the bloodstream and carried to the cells throughout the body. Without digestion and absorption, the food we consume would not be able to provide the necessary nutrients for our cells to function properly.

Explanation
The small intestine is responsible for the absorption of most nutrients in the digestive system. It has a large surface area due to its long length and the presence of villi and microvilli, which increase the absorption capacity. The small intestine receives partially digested food from the stomach and further breaks it down using enzymes produced by the pancreas and bile from the liver. This allows for the absorption of nutrients such as carbohydrates, proteins, fats, vitamins, and minerals into the bloodstream, where they can be transported to various cells and tissues in the body for energy and growth.

Explanation
The circulatory system is responsible for transporting glucose and other substances in the blood to the cells of the body. This system includes the heart, blood vessels, and blood. The heart pumps oxygenated blood containing glucose and other nutrients to the cells, while also removing waste products. The blood vessels, including arteries and veins, carry the blood throughout the body, ensuring that all cells receive the necessary nutrients and oxygen for proper functioning. Therefore, the circulatory system is the correct answer for this question.

Explanation
The circulatory system is responsible for regulating body temperature. This system includes the heart, blood vessels, and blood. When the body temperature rises, the circulatory system helps to cool it down by increasing blood flow to the skin's surface, allowing heat to dissipate through sweat and evaporation. Conversely, when the body temperature drops, the circulatory system constricts blood vessels to minimize heat loss and maintains a stable internal temperature. Therefore, the circulatory system plays a crucial role in maintaining and regulating body temperature.

Explanation
Neurons are specialized cells that are responsible for transmitting information in the nervous system. They are the building blocks of the nervous system, which includes the brain, spinal cord, and nerves. Neurons are not found in the circulatory or respiratory systems. Therefore, the correct answer is "nervous."

Explanation
The brain is a part of the central nervous system. It is responsible for processing and coordinating information from the senses, controlling movements, and regulating bodily functions. The eyes are sensory organs that transmit visual information to the brain, but they are not a part of the central nervous system. The lungs are part of the respiratory system, and although they play a vital role in gas exchange, they are not directly involved in the central nervous system.

Explanation
The ability to maintain a constant body temperature is an example of homeostasis. Homeostasis refers to the body's ability to regulate and maintain a stable internal environment despite external changes. In the case of maintaining a constant body temperature, the body adjusts its metabolic processes, such as sweating or shivering, to keep the temperature within a narrow range. This balance is crucial for the proper functioning of various physiological processes and overall health.