Microbiology and Immune Response Overview

<p>The prevention of pathogen overgrowth by resident microbiota. (D)</p> Signup and view all the answers

<p>Displacement from normal body sites. (A)</p> Signup and view all the answers

<p>They protect the conjunctiva from bacterial colonization. (C)</p> Signup and view all the answers

<p>Middle ear (C)</p> Signup and view all the answers

<p>They may cause infections. (B)</p> Signup and view all the answers

<p>Aerobic and anaerobic bacteria, yeasts, molds, protozoa, and viruses (B)</p> Signup and view all the answers

<p>Acidic pH and gastric enzymes (D)</p> Signup and view all the answers

<p>Anaerobic flora (A)</p> Signup and view all the answers

<p>Kidneys, ureters, and urinary bladder (B)</p> Signup and view all the answers

<p>Lactobacillus spp. (C)</p> Signup and view all the answers

<p>They cannot survive in acidic or alkaline pH environments. (B)</p> Signup and view all the answers

<p>In sites exposed to the outside world. (C)</p> Signup and view all the answers

<p>Staphylococcus epidermidis (D)</p> Signup and view all the answers

<p>Natural oils and sweat. (C)</p> Signup and view all the answers

<p>Staphylococcus epidermidis (A)</p> Signup and view all the answers

<p>Bloodstream infections. (A)</p> Signup and view all the answers

<p>Cutibacterium acnes (C)</p> Signup and view all the answers

<p>Resident normal flora produce substances harmful to transients. (C)</p> Signup and view all the answers

<p>To assist in nutrient absorption (A)</p> Signup and view all the answers

<p>Microbes that continuously inhabit the human body (A)</p> Signup and view all the answers

<p>Hormonal differences and geographical habitat (C)</p> Signup and view all the answers

<p>Opportunistic microbes may cause infections (D)</p> Signup and view all the answers

<p>Roughly 2 kg (D)</p> Signup and view all the answers

<p>They contribute to natural resistance mechanisms (B)</p> Signup and view all the answers

<p>Prevotella, Ruminococcus, Bacteroidetes (A)</p> Signup and view all the answers

<p>It provides insight into possible infections from specific body site injuries (B)</p> Signup and view all the answers

<p>It keeps the pH acidic to protect against opportunistic infections. (C)</p> Signup and view all the answers

<p>It stimulates the development of the immune system. (B)</p> Signup and view all the answers

<p>Vitamin K (A)</p> Signup and view all the answers

<p>They resulted in the nonobese mice becoming obese. (D)</p> Signup and view all the answers

<p>Proteobacteria and Actinobacteria (A)</p> Signup and view all the answers

<p>Increased susceptibility to infectious diseases. (A)</p> Signup and view all the answers

<p>Diversity of microbial species in non-diseased individuals. (B)</p> Signup and view all the answers

<p>By producing antibiotic substances. (B)</p> Signup and view all the answers

Microorganisms, mainly bacteria, that live in the human body. They are often harmless and can even be beneficial.

Microorganisms that are always present in a specific environment, like the human body, and are typically harmless.

Microorganisms that are temporarily present in a specific environment, often due to external factors.

Resident flora plays a crucial role in maintaining overall health by preventing harmful pathogens from taking over.

The human gut contains a very large number of bacteria, viruses, and other microorganisms.

The presence of normal microbiota in the body helps protect against disease-causing organisms.

Disruptions in the balance of normal microbiota can lead to opportunistic infections.

Microbiota composition in the body can vary based on factors like age, diet, and hygiene.

Microorganisms that are temporarily present on or within a human body, often due to external factors like contact with surfaces.

Microorganisms that are always present in a specific site of the human body and are typically harmless. They are adapted to living in that environment.

Moist, warm areas of the body often attract transient microbes from the external environment. These areas provide favorable conditions for their temporary growth.

A combination of tears, mucus, and oil that helps to prevent bacterial colonization of the eye's conjunctiva.

Skin can be a temporary home for transient bacteria, but they are often eliminated due to the skin's dry, acidic environment and the production of sweat and oil that washes them away.

Generally sterile, but microbes can enter through coughing, sneezing, or blowing the nose, leading to infection.

The presence of many microorganisms, including normal flora, opportunistic pathogens, and carried pathogens like Corynebacterium diphtheriae.

The outer layer of skin primarily harbors aerobic bacteria like Staphylococcus epidermidis and Staphylococcus aureus, while deeper layers, hair follicles, and sweat/sebaceous glands are home to anaerobic bacteria like Cutibacterium acnes.

Although generally harmless, skin microbiota can cause bloodstream infections if the skin barrier is broken, allowing them to enter the body.

A common inhabitant of the nasopharynx, sometimes causing pneumonia in immune-compromised individuals.

The lower respiratory tract is typically sterile due to the cleansing effect of the mucous membranes.

The conjunctiva of the eye, the transparent membrane covering the white part of the eye, is mainly home to bacteria like Staphylococcus epidermidis, followed by Staphylococcus aureus, Corynebacterium diphtheroids, and Streptococcus pneumoniae.

The presence of both aerobic and anaerobic bacteria in the oral cavity, with common examples being Corynebacterium diphtheriae, Staphylococcus aureus, and Staphylococcus epidermidis.

The eye, like the skin, has a limited amount of resident microbiota, and some skin normal flora are also present in the eye but in smaller quantities.

The stomach's acidic environment and gastric enzymes limit bacterial growth.

The large intestine is the part of the body with the highest concentration of bacteria, with 99% being anaerobic. Various fungi, protozoa, and viruses also reside there.

The vaginal microbiota maintains an acidic pH, preventing opportunistic infections like Candida albicans (fungal vaginitis) and Bacteroides spp. / Gardnerella vaginalis (bacterial vaginosis).

The lungs, middle ear, cerebrospinal fluid, bones and joints, pleura, paranasal sinuses, meninges, kidney, blood, larynx, endocardium, trachea, bronchus, gallbladder, bladder, fallopian tubes, epididymis, and prostate are typically sterile body zones.

Normal microbiota prevents pathogens from invading by producing substances that kill them and competing for resources.

Microbiota in newborns helps develop their immune system.

Gut microbiota provides Vitamin K and other nutrients that aid digestion and absorption.

Studies show that the microbiome is linked to several body functions and diseases.

The microbiome plays a role in weight control (obesity), inflammatory bowel disease, immune response, and resistance to infectious diseases.

The gut microbiome is thought to influence inflammatory bowel diseases like Crohn's disease and ulcerative colitis.

The intestinal flora protects against overgrowth of harmful bacteria like Clostridioides difficile, which causes pseudomembranous colitis. When antibiotics disrupt the gut microbiota, this resistance is lost, leading to C. difficile overgrowth and colitis.

Germ-free mice lack lymphoid follicles in the small intestine, secretory IgA, and CD8 intraepithelial lymphocytes, demonstrating the influence of microbiota on immune system development.

The gut microbiota influences the balance of T cell subsets, particularly Th1, Th2, and Th17 cells, which play crucial roles in immune responses.

The presence of specific gut microbiota members can affect the composition of T cells, impacting the immune system's ability to respond to pathogens and maintain homeostasis.

A fecal transplant from a healthy individual can successfully treat intractable colitis, highlighting the importance of restoring a balanced gut microbiota.