
Concept explainers
Describe the location of the apical region of an epithelial tissue. How can this region be easily identi�ed in a micrograph?

To review:
The apical surface of an epithelial tissue and its identification in a micrograph.
Introduction:
The epithelial tissue is a lining of cells covering body surfaces and cavities. The cells forming the epithelial tissue are closely bound together through specialized intercellular junctions. This tissue performs various functions such as protection, filtration, diffusion, secretion, absorption, and sensory reception. It rests upon a layer of connective tissue that provides nutritional support.
Explanation of Solution
A characteristic feature of epithelial cells is their polarization into apical and basal region which are distinguished on the basis of their position. The protein composition and function of apical and basal membrane varies and the tight junctions prevent the free passage of molecules between adjacent cells.
The apical region of an epithelial tissue is present at the top of the epithelial tissue and is directly exposed to the external environment. In simple epithelial tissue composed of a single layer of cells, the apical region of the cell faces toward the lumen or the external environment and the basal region sits on a layer of connective tissue. The stratified epithelium is composed of multiple layer of cells in which the apical region of topmost layer is exposed to the external environment and the basal region of the bottom layer rests on the connective tissue.
In a micrograph, the apical region of an epithelial tissue is identified as the region exposed to an empty space.
Want to see more full solutions like this?
Chapter 4 Solutions
Pearson eText Human Anatomy -- Instant Access (Pearson+)
- What is this?arrow_forwardMolecular Biology A-C components of the question are corresponding to attached image labeled 1. D component of the question is corresponding to attached image labeled 2. For a eukaryotic mRNA, the sequences is as follows where AUGrepresents the start codon, the yellow is the Kozak sequence and (XXX) just represents any codonfor an amino acid (no stop codons here). G-cap and polyA tail are not shown A. How long is the peptide produced?B. What is the function (a sentence) of the UAA highlighted in blue?C. If the sequence highlighted in blue were changed from UAA to UAG, how would that affecttranslation? D. (1) The sequence highlighted in yellow above is moved to a new position indicated below. Howwould that affect translation? (2) How long would be the protein produced from this new mRNA? Thank youarrow_forwardMolecular Biology Question Explain why the cell doesn’t need 61 tRNAs (one for each codon). Please help. Thank youarrow_forward
- Molecular Biology You discover a disease causing mutation (indicated by the arrow) that alters splicing of its mRNA. This mutation (a base substitution in the splicing sequence) eliminates a 3’ splice site resulting in the inclusion of the second intron (I2) in the final mRNA. We are going to pretend that this intron is short having only 15 nucleotides (most introns are much longer so this is just to make things simple) with the following sequence shown below in bold. The ( ) indicate the reading frames in the exons; the included intron 2 sequences are in bold. A. Would you expected this change to be harmful? ExplainB. If you were to do gene therapy to fix this problem, briefly explain what type of gene therapy youwould use to correct this. Please help. Thank youarrow_forwardMolecular Biology Question Please help. Thank you Explain what is meant by the term “defective virus.” Explain how a defective virus is able to replicate.arrow_forwardMolecular Biology Explain why changing the codon GGG to GGA should not be harmful. Please help . Thank youarrow_forward
- Stage Percent Time in Hours Interphase .60 14.4 Prophase .20 4.8 Metaphase .10 2.4 Anaphase .06 1.44 Telophase .03 .72 Cytukinesis .01 .24 Can you summarize the results in the chart and explain which phases are faster and why the slower ones are slow?arrow_forwardCan you circle a cell in the different stages of mitosis? 1.prophase 2.metaphase 3.anaphase 4.telophase 5.cytokinesisarrow_forwardWhich microbe does not live part of its lifecycle outside humans? A. Toxoplasma gondii B. Cytomegalovirus C. Francisella tularensis D. Plasmodium falciparum explain your answer thoroughly.arrow_forward
- Select all of the following that the ablation (knockout) or ectopoic expression (gain of function) of Hox can contribute to. Another set of wings in the fruit fly, duplication of fingernails, ectopic ears in mice, excess feathers in duck/quail chimeras, and homeosis of segment 2 to jaw in Hox2a mutantsarrow_forwardSelect all of the following that changes in the MC1R gene can lead to: Changes in spots/stripes in lizards, changes in coat coloration in mice, ectopic ear formation in Siberian hamsters, and red hair in humansarrow_forwardPleiotropic genes are genes that (blank) Cause a swapping of organs/structures, are the result of duplicated sets of chromosomes, never produce protein products, and have more than one purpose/functionarrow_forward
- Principles Of Radiographic Imaging: An Art And A ...Health & NutritionISBN:9781337711067Author:Richard R. Carlton, Arlene M. Adler, Vesna BalacPublisher:Cengage LearningSurgical Tech For Surgical Tech Pos CareHealth & NutritionISBN:9781337648868Author:AssociationPublisher:Cengage
- Human Physiology: From Cells to Systems (MindTap ...BiologyISBN:9781285866932Author:Lauralee SherwoodPublisher:Cengage Learning

