HBS Immune System Test

Bacteria

single-celled prokaryotic microorganisms

Fungi

eukaryotic organisms such as yeasts and molds that often thrive in warm, moist environments.

Helminths

living, multicellular eukaryotic worms

Prions

abnormal forms of protein that cause other proteins to misfold

Protists

single-celled microscopic eukaryotic parasites

Viruses

non-living microscopic agents made up of an outer protein shell called a capsid and their DNA or RNA

Innate Immunity

non-specific immune defense mechanisms that people are born with

Acquired Immunity

specific immune defense mechanisms that are acquired over a lifetime

What cells are in innate immunity?

Macrophages, Neutrophils, dendritic cells

What cells are in acquired immunity?

T cells and B cells

What type of white blood cells are macrophages, neutrophils, and monocytes?

phagocytes

What type of white blood cells are b cells and t cells?

lymphocytes

Active immunity

acquired after infection or vaccination

Passive immunity

acquired by a child from its mother through placenta or breast feeding

Helper T cell

release cytokines that activate b cells and cytotoxic t cells

Cytotoxic T cell

kills infected or abnormal cells by releasing toxic substances that cause the target cell to die

Memory B cell

long-lived B cell that remembers a specific pathogen after an infection or vaccination

Plasma B cell

fully activated B cell produces and secretes large amounts of antibodies specific to a pathogen

Cytokines

signaling proteins released by immune cells

Neutrophil

most abundant WBC in humans and the first cells to respond

Macrophage

large WBC that engulfs and digests pathogens, dead cells, and debris; presents antigens to T cells

Dendritic cell

WBC that captures pathogens and presents their antigens to T cells; connects innate and adaptive immune systems

What cell activates helper T cells and what cells do helper T cells activate?

Gets activated by dendritic cells and activates B cells and cytotoxic T cells.

What are the stages of viral reproduction?

1. Assembly

2. Entry

3. Uncoating

4. Replication

5. Assembly

6. Release

1. Attachment

the virus binds to specific receptors on the host cell

2. Entry

the virus or its genetic material enter the host cell through endocytosis (cell engulfs virus) or the virus fuses with the cell membrane

3. Uncoating

the viral capsid is removed, releasing the viral DNA/RNA into the host cell.

4. Replication

the virus uses host cell’s machinery to copy viral singl-stranded RNA, double-stranded RNA, or single stranded DNA and produce viral proteins

5. Assembly

New virus parts self-assemble into new visions (intact & infective virus particles); assembly can happen in the nucleus, plasma membrane, or intracellular membrane like Golgi

6. Release

new virions are released into the extracellular environment from lysis (cell bursts and dies) or budding (virus exits without killing cell)

How do antivirals interrupt the stages of viral reproduction?

1. block the virus from binding to host cell receptors

2. prevents entry of virus

3. prevent the virus from releasing genetic material in the cell

4. inhibit viral enzymes needed to copy genetic material (most common)

5. interfere with the assembly of new virions

6. block the virus from leaving the host cell

RNA virus replication vs DNA virus replication

RNA viruses replicate in the cytoplasm using mRNA immediately and directly translated into proteins (faster and more mutations)

DNA viruses replicate in the nucleus using DNA to make mRNA to make proteins, using host cellular machinery.

How do the immune system and lymphatic system work together?

Lymphatic vessels transport immune cells and fluids throughout the body. Lymph nodes filter lymph which contain immune cells. Activated cells and antibodies leave lymph nodes, travel through lymph, and enter the blood stream.

What is lymph and what does it carry?

fluid that carries pathogens, cell debris, and antigens to lymph nodes for removal

Function of lymph nodes

contain immune cells like lymphocytes and phagocytes and filter harmful substances and pathogens from lymph

Where do t cells mature?

thymus

Where do b cells mature?

bone marrow

Solution

liquid mixture which solute is distributed within the solvent

solute

substance being dissolved (minor component)

solvent

dissolving medium (major component)

Molar solution

1M = (1xMW)/Liter

mg/mL solution

concentration = mass/volume

nX solution

C1V1=C2V2

Serial dilution

dilution factor = amount of sample (mL)/total volume (mL)

Fold strength

equivalent to dilution factor

What is a 10-fold serial dilution?

1:10 dilution or a dilution factor of 10.

Outermost layer of the skin

epidermis

Epidermis function

protective barrier that prevents water loss and protects against pathogens

Epidermis features

keratinocytes (structure), corneocytes (barrier), melanocytes (pigment)

Middle layer of the skin

dermis

Dermis function

provides strength, elasticity, and structure, contains nerves and blood vessels

Dermis features

collagen, elastin, sweat glands, hair

Deepest layer of the skin

hypodermis

Hypodermis function

insulates body, stores fat for energy, anchors skin to muscle

Hypodermis features

adipose (fat) and connective tissue

Cornea function

proective barrier and eye’s primary focusing element

Iris function

regulates the amount of light entering the pupil

Pupil function

controls the diameter of the opening to regulate light entry

Lens function

use refraction to bend, focus on disperse light rays

Retina function

Captures incoming light, converts it into a neutral signal, and transmits these signals to the brain to create visual images

Aqueous humor

fluid between the cornea and lens that maintains intraocular pressure

Vitreous humor

fluid between the lens and retina that maintains eye’s shape and a pathway for light to reach the retina

Optic nerve function

transmits visual information from the retina to the brain’s visual cortex

Sclera function

protects internal eye structure, maintains shape, and attaches to muscles

Path of light in the eye

Cornea→Aqueous Humor→Pupil→Iris→Lens→Vitreous Humor→Retina→Photoreceptors (rods&cones)

Photoreceptors

specialized neurons in the retina that convert light into electrical signals