C3.2 SL / HL Flashcards
Pathogens
a microorganism that causes disease in a host organism
Bacteria
small single-celled organisms. Bacteria are found almost everywhere on Earth and are vital to the planet’s ecosystems
Fungi
any member of the group of eukaryotic organismsthat includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms.
Protists
any member of a group of diverse eukaryotic, predominantly unicellular microscopic organisms.
malaria
a life-threatening disease caused by parasites that are transmitted to humans through the bites of infected female Anopheles mosquitoes
Viruses
microscopic germs that have to infect a host, like humans, animals or plants to reproduce
SARS-CoV-2
definedas a group of related RNA viruses that infect mammals and birds. When infecting humans, these viruses cause respiratory diseases
Skin
the body’s largest organ and primary protective barrier against the environment.It is made up of multiple layers of ectodermal tissue and is part of the integumentary system, which is the body’s outer covering
Epidermis
the outermost layer of skin or the thin surface layer of tissue in plants
Dermis
The inner layer of the two main layers of the skin. The dermis has connective tissue, blood vessels, oil and sweat glands, nerves, hair follicles, and other structures.
Dermal cells
cells in the skin or in plants that protect the body or plant from injury, regulate temperature, and perform other functions
mitosis
a process in which a eukaryotic cell nucleus splits into two, and the parent cell divides into two identical daughter cells
lysosomes
a sac-like organelle in a cell that contains enzymes that break down cellular components
Mutualistic
a biological relationship where two or more species benefit from each other and neither is harmed
Mucous membrane
a moist tissue that lines the inside of organs and cavities in the body
glycoproteins
proteins with sugar molecules attached to them, which are known as oligosaccharides
phagocytes
a type of white blood cell that can engulf and destroy foreign substances, such as dead cells, microorganisms, and parasites
Ciliated cells
specialized cells that have tiny hair-like structures called cilia that beat in a rhythmic motion to move substances in one direction
trachea
a tube-shaped airway that connects the larynx (voice box) to the bronchi, which then lead to the lungs
esophagus
a muscular tube that carries food from the mouth to the stomach
Blood clotting
a biological process that prevents excessive bleeding when a blood vessel is damaged
fibrin
a protein that forms a fibrous network to stop bleeding and heal wounds by trapping blood cells
erythrocytes
red blood cells, the most common type of cell in the blood
leukocytes
known as white blood cells (WBCs), area type of blood cell that are part of the body’s immune system and help fight infection and disease
Plasma proteins
a group of macromolecules found in blood plasma that perform many functions
prothrombin
a protein in the blood that helps it clot and is produced by the liver
fibrinogen
a protein in the blood that helps form clots to stop bleeding and heal wounds
clotting factors
any of several plasma components(such as fibrinogen, prothrombin, thromboplastin, and factor VIII) that are involved in the clotting of blood
thrombin
enzyme formed from prothrombin that facilitates the clotting of blood by catalyzing conversion of fibrinogen to fibrin
clot
A mass of blood that forms when blood platelets, proteins, and cells stick together
Immune system
a complex network of cells, tissues, organs, and proteins that protects the body from infection, disease, and other invaders
Innate immune system
the body’s first line of defense against harmful substances, and it’s present at birth and lasts a person’s entire life. It’s made up of cells and barriers that work together to protect the body from pathogens, parasites, and other harmful substances
passive immunity
a type of immunity that occurs when a person receives antibodies from another person or source, rather than producing them through their own immune system
antibodies
proteins that are part of the immune system and are produced by plasma cells in response to foreign substances called antigens
Phagocytes
a type of white blood cell that can engulf and destroy foreign substances, such as microorganisms, dead cells, and cellular debris
antigens
a substance that causes the body to produce an immune response against it
Adaptive immune system
a subsystem of the immune system that responds to foreign substances and microorganisms, such as pathogens and tumor cells
active immunity
when the body’s immune system produces antibodies to fight off a disease or pathogen
vaccines
a weakened or killed version of a virus or bacteria that trains the body to recognize and fight the disease if it encounters it again
memory B cells
a type of white blood cell that play a key role in immunological memory
Lymphocytes
a type of white blood cell that are part of the immune system and are produced in the bone marrow
Amoeboid movement
a crawling or oozing type of movement that cells use to change shape and move
chemotaxis
the process by which cells or organisms move in response to chemical stimuli, either toward or away from a chemical source
phagocytosis
a biological process in which cells engulf and digest foreign substances or other cells
endocytosis
a biological process in which a cell takes in substances from its environment by forming vesicles within its plasma membrane
Phagosome
a vesicle that forms when a phagocyte engulfs a particle through phagocytosis
exocytosis
a cellular process that moves large molecules and waste from inside a cell to the outside
lymph nodes
small, bean-shaped organs that are part of the body’s immune system and filter lymph fluid
lymphatic system
a network of vessels, nodes, and ducts that pass through almost all bodily tissues. It allows the circulation of a fluid called lymph
T-lymphocytes
part of the immune system and develop from stem cells in the bone marrow. They help protect the body from infection and may help fight cancer.
B-lymphocytes
A type of white blood cell that makes antibodies. B lymphocytes are part of the immune system and develop from stem cells in the bone marrow
Plasma cells
a type of white blood cell that produce large amounts of antibodies to help protect the body from pathogens
immunity
the body’s ability to resist or be insusceptible to a disease or harmful substance
Capsid
a protein shell that surrounds the genetic material of a virus
Blood type
a classification system that determines whether a person’s blood is compatible with another person’s blood
ABO gene
encodes the type of blood (A, B, AB, or O) a person has
Rhesus factor gene
encoades a protein that determines whether a person is Rh-positive or Rh-negative, based on whether their red blood cells have the Rh protein
agglutination
a biological process that occurs when particles, like bacteria or red blood cells, clump together in the presence of an antibody
universal recipient
a person with blood type AB positive (AB+) who can receive blood from any donor
universal donor
someone with type O negative blood, which can be safely given to anyone in an emergency
Helper T-lymphocytes
a type of white blood cell and immune cell that help coordinate the body’s immune response to infections and other threat
cytokines
A type of protein that is made by certain immune and non-immune cells and has an effect on the immune system. Some cytokines stimulate the immune system and others slow it down.
differentiate
the process by which immature cells develop into mature cells with specific functions
Primary immune response
the body’s initial reaction to a foreign substance, or antigen, and is characterized by the production of antibodies and memory lymphocytes
Secondary immune response
the immune system’s reaction when a person is re-exposed to a pathogen or antigen that they have encountered before
Human immunodeficiency virus (HIV)
a virus that attacks the body’s immune system, making it harder to fight off infections and diseases
Provirus
a viral genome that is integrated into the DNA of a host cell, making it an inactive, but potentially replicating, form of the virus
host cell
a living cell invaded by or capable of being invaded by an infectious agent (as a bacterium or a virus)
CD4 Helper T-lymphocytes
A type of lymphocyte. CD4 T lymphocytes (CD4 cells) help coordinate the immune response by stimulating other immune cells, such as macrophages, B lymphocytes (B cells), and CD8 T lymphocytes (CD8 cells), to fight infection. HIV weakens the immune system by destroying CD4 cells.
Acquired immunodeficiency syndrome (AIDS)
a chronic condition that occurs when the human immunodeficiency virus (HIV) attacks and destroys the body’s CD4 cells, a type of white blood cell that helps fight infection
opportunistic infections
an infection that occurs more frequently or is more severe in people with weakened immune systems
penicillin
a group of antibiotics that are used to treat bacterial infections
Alexander Fleming
Scottish physician and microbiologist who discovered penicillin, the first antibiotic, in 1928. His discovery revolutionized medicine and saved millions of lives
Antibiotics
chemical substances that kill or limit the growth of microorganisms, such as bacteria, to treat infections
Antibiotic resistance
a biological process that occurs when bacteria mutate and become resistant to antibiotics, making them ineffective in treating infections
Natural selection
a biological process that causes species to change over time in response to environmental changes or competition between organisms
MRSA
methicillin-resistant Staphylococcus aureus, a type of bacteria that is resistant to several antibiotics, including methicillin, amoxicillin, and penicillin
Zoonotic diseases
infections that can spread from animals to humans, or vice versa, and are caused by organisms like bacteria, viruses, fungi, and parasites
Rabies
a viral disease that causes encephalitis in humans and other mammals
Tuberculosis
a contagious bacterial disease that primarily affects the lungs, but can also impact other parts of the body
tubercles
a small, rounded prominence or nodule that can be found on the external or internal organs of an animal or plant
Japanese encephalitis
a viral disease caused by the Japanese encephalitis virus (JEV), a mosquito-borne flavivirus
COVID-19
an infectious disease caused by the SARS-CoV-2 virus. Most people infected with the virus will experience mild to moderate respiratory illness and recover without requiring special treatment
asymptomatic
having no signs or symptoms of a disease or condition
Edward Jenner
English physician and scientist who pioneered the concept of vaccines and created the first vaccine, the smallpox vaccine
cowpox
a viral skin disease that causes a mild rash and is caused by the cowpox virus, a member of the Orthopoxvirus family
smallpox
an infectious disease caused by the variola virus. Smallpox has been eradicated, with no cases occurring since 1977. The disease caused rashes and could spread through coughing and sneezing. Smallpox no longer occurs naturally, but it is possible that variola virus could be used in a biological attack
vaccine
a biological preparation that helps the body’s immune system recognize and fight off disease-causing microorganisms
Herd immunity
the protection a population has against a disease outbreak when a large percentage of the population is vaccinated against it
Measles
a highly contagious viral infection that affects the respiratory system, skin, and immune system
R0 (R nought / zero)
mathematical term that indicateshow contagious an infectious disease is. It’s also referred to as the reproduction number
Epidemiologist
a scientist who studies the patterns, causes, and control of disease in groups of people
Percent change
the amount of increase or decrease in a value over time, expressed as a percentage of the original value
Percent difference
a way to compare two values by expressing the difference between them as a percentage of their average
