Explanation

• Contractile vacuoles are specialized organelles found exclusively in protozoa, such as amoebae and paramecia.
• They are responsible for osmoregulation, removing excess water and ions from the cell to maintain proper cellular turgor pressure.
• Contractile vacuoles are able to contract and expand to expel water and waste from the cell.

Explanation

• The sentence should read: "Their daughters are truly interested in one of the rare species that inhabit those islands."
• "Inhabit" means to live or dwell in a place, which fits the context of the sentence.

Explanation

• The Carboniferous period of coal deposition was approximately 300 million years ago.
• This period occurred from about 354 to 290 million years ago during the late Paleozoic Era.
• The term "Carboniferous" comes from England, in reference to the rich deposits of coal that occur there.
• These deposits of coal occur throughout northern Europe, Asia, and midwestern and eastern North America.

Explanation

• A Barr body is a densely staining body found in the interphase nuclei of somatic cells of female mammals, including humans.
• It is a condensed, inactivated X chromosome, which is one of the two X chromosomes present in the nuclei of female cells.
• The Barr body is a result of X-chromosome inactivation, a process that occurs in female mammals to avoid a doubling of gene expression.

Explanation

• Phylloquinone, also known as Vitamin K1, is essential for blood coagulation in the body.
• It plays a crucial role in the production of clotting factors II, VII, IX, and X, which are necessary for the formation of blood clots and stopping bleeding.

Explanation

• Krause's discs are another name for the bulbous endings of sensory nerve fibers that surround the Z discs (or Z lines) in muscle fibers.
• These sensory nerve endings are responsible for detecting muscle length and tension, and are also known as muscle spindles or neuromuscular spindles.

Explanation

• When a population is small, it is more susceptible to genetic drift, which is the random change in the frequency of a gene or trait in a population over time.
• This is because there are fewer individuals and therefore less genetic diversity, making it more likely that chance events will significantly influence the gene pool.

Explanation

Microtubules are a type of cytoskeletal filament that play a crucial role in moving organelles, vesicles, and chromosomes within cells.

They are involved in various cellular processes, including:

• Intracellular transport (e.g., moving mitochondria, vesicles, and chromosomes)
• Cell division (e.g., separating chromosomes during mitosis)
• Cilia and flagella structure and movement
• Maintaining cell shape and mechanical integrity

Explanation

• Bronchioles are the narrowest and most numerous tubes of the lungs, and they play a crucial role in conducting air to the alveoli, where gas exchange occurs.
• They are the smallest branches of the bronchi and are responsible for distributing air to the different regions of the lungs.

Explanation

• The mesoglea is a thin, gelatinous layer of tissue in Hydra that lies between the outer epidermis and the inner gastrodermis.
• It is a cell-free, acellular layer that provides structural support and flexibility to the body.
• The mesoglea is composed of a matrix of glycoproteins and proteoglycans, but it does not contain any cells.