block 1 prac test Flashcards
What is a cross section?
A slice perpendicular to the long axis.
What is a longitudinal section?
A slice taken parallel to the long axis.
Why is it necessary to examine a specimen in both cross and longitudinal sections?
To understand its three-dimensional structure.
What are the steps of protein synthesis?
Transcription (DNA to mRNA), Translation (mRNA to protein), Amino acid assembly at the ribosome.
What is the role of the ribosome in protein synthesis?
It is the site of translation and assembles amino acids into proteins.
What is the function of tRNA during translation?
Transfers specific amino acids to the ribosome and matches them to mRNA codons.
What is the role of mRNA in protein synthesis?
Carries genetic code from nucleus to ribosome and serves as the template for amino acid assembly.
What are the characteristics of epithelial tissue?
Closely packed cells, minimal extracellular matrix, covers surfaces and lines cavities.
What distinguishes muscle tissue from other tissue types?
Unique ability to contract, enabling movement.
What are the functions of connective tissue?
Provides support and structure, binds tissues, stores energy, aids in transport.
What are the four main tissue types studied in histology?
Epithelial, connective, muscle, and nervous.
Why is staining important in histology?
It enhances visibility and differentiates between tissue types.
What does methylene blue stain?
The nucleus and sometimes cytoplasmic components.
What is the primary purpose of staining in histology?
To differentiate tissue components.
What does a cross section of a centriole reveal?
The arrangement and number of internal microtubule components.
What does a longitudinal section of a centriole show?
The length and orientation of microtubules.
When is SEM more useful than TEM?
For examining surface details of specimens.
What does SEM capture that TEM does not?
External topography of a specimen.
When is TEM more useful than SEM?
For studying internal ultrastructure of specimens.
What does TEM reveal about cilia?
Detailed cross and longitudinal sections.
How does a dissecting microscope orient a specimen?
It provides an upright image.
How does specimen movement appear in a dissecting microscope?
Moving left shifts the image right.
How does a compound microscope orient a specimen?
It inverts and reverses the image.
What is the total magnification with a 4x objective and 10x ocular lens?
40x.