What is phagocytosis? What does it involve?
What will be an ideal response?
Phagocytosis is a process by which a cell can engulf substances and internalize them into the cytoplasm. Cells that are capable of phagocytosis are collectively known as phagocytes and include neutrophils, eosinophils, dendritic cells, and macrophages. Phagocytosis is part of the body's second line of defense, and it is nonspecific. It includes the following steps:
Chemotaxis: a cell moves either toward or away from a chemical stimulus.
Adherence: the phagocyte attaches to the pathogen, through binding of complementary chemicals on the membranes of the pathogen.
Ingestion: after the pseudopodia adhere to the pathogen, the encompassed microbe is internalized as the pseudopodia fuse to form a sac called a phagosome.
Digestion: lysosomes with over 30 digestive enzymes attach to the phagosome and break down the microbe. At the end of this process, the remains of the phagosome are known as the residual body.
Elimination: the phagocyte rids itself of undigested material by exocytosis, which is the opposite of ingestion.
Bloom's Taxonomy: Comprehension
Section: The Body's Second Line of Defense
Learning Outcome: 15.12
You might also like to view...
Examine Figure 44.1 in your text. According to this phylogeny, which of the following correctly lists the sequence in which multicellularity, tissues, and bilateral symmetry arose, from the oldest character to the most recent character?
A. multicellularity, tissues, bilateral symmetry B. multicellularity, bilateral symmetry, tissues C. tissues, bilateral symmetry, multicellularity D. tissues, multicellularity, bilateral symmetry E. That information cannot be determined from the phylogeny.
Which of the following molecules directly converts NADP+ to NADPH?
A. ferrodoxin B. cytochrome complex C. NADP reductase D. plastocyanin E. RUBISCO
As decomposition proceeds, which molecule is lost to the atmosphere?
A) H2O B) CH4 C) CO2 D) NH3
Surface of the skin, lining of the mouth, throat, rectum, anus, vagina
A. Pseudostratified columnar B. Simple columnar C. Simple cuboidal D. Simple squamous E. Stratified squamous F. Transitional