The nuclei (the structure inside a cell that contains DNA) of the cheek cells have been stained using a special dye so that they appear purple. What shape are they

Oval.

Explanation:

The nucleus of a cell is a membranous structure normally found in the center of eukaryotic cells and is where most of the cellular genetic material is found, organized in DNA molecules (deoxyribonucleic acid) associated with proteins such as histones, which make up the chromosomes.

The function of the nucleus is to maintain the integrity of the genes in the DNA and to regulate gene expression to control cellular activities. It then controls when DNA is transcribed into RNA (ribonucleic acid) and when it is exported to the cytoplasm to be translated into proteins.

The nucleus is composed of a nuclear envelope consisting of a double membrane that surrounds it, as well as pores that allow the passage of RNA for the regulation of gene expression.

The cells of the inner cheek are classified as non-keratinized stratified squamous epithelium. An epithelium is a tissue made up of joined cells that line the outer surface of the body and inner organs. Squamous cells are flat, scale-like, whereas stratified cells are arranged in multiple layers. Non-keratinized means that the cells constitute soft tissue found in the moist parts of our body, such as the mouth, stomach, among others. In a normal healthy cell, the nucleus is uniformly stained, oval in shape and smaller in relation to the cytoplasm.

straight probes are used primarily for measuring flow as it is approaching the test area. its geometry allows the probe to be mounted so that it is in the direct line of airflow.