Arthropods as Parasites and Vectors

Insect life cycle where juvenile stages resemble adults, called nymphs.

Insect life cycle with distinct juvenile (larva) and adult stages, with a pupal stage in between.

The juvenile stage of insects undergoing incomplete metamorphosis; resembles a smaller adult.

Juvenile stage of insects undergoing complete metamorphosis; often adapted for feeding and growth.

Typical life cycle involves eggs, nymphs, and adults; adults lay eggs repeatedly on host.

Life cycle is about two weeks, eggs (nits) cemented to hair, nymphs moult, adults reproduce.

Four pairs of legs in both nymphs and adults, fused cephalothorax and abdomen, no antennae.

Understanding insect life cycles helps identify parasites and their stages of development.

The series of stages in the life of an arthropod, from egg to adult, often with molting.

A stage in a flea's life cycle that feeds on digested blood.

An organism that provides food and/or shelter for another organism.

The process of shedding an exoskeleton or skin.

Understanding an arthropod's life cycle can help devise effective control measures.

Ticks have a complex life cycle with different stages, a three host tick has adult, larva, and nymph stages, which feed on different animals and moult between stages.

Specific characteristics that help parasites survive and reproduce in their host environment, like a chitinous exoskeleton for protection.

A parasitic relationship where the parasite lives on its host for the entire life cycle, unlike ticks which are temporary.

A parasitic association where the parasite visits its host only for a blood meal and then leaves, like midges or poultry mites.

A type of tick that produces large numbers of offspring to maintain its population, meaning it may have more offspring than other types of insects.

An example of a permanent ectoparasite, a wingless fly with specific body adaptations for a parasitic lifestyle.

An example of a temporary ectoparasite that feeds on birds' blood at night. It spends most time away from host in daytime.

Parasites that live on the surface of another organism.

Parasites that live inside the body of another organism.

Mouthparts designed for chewing, often strong and powerful, with mandibles acting like jaws. Examples include chewing lice.

Mouthparts specialized for tearing host tissue, usually large, strong, and curved hooks. Found in myiasis fly larvae.

Mouthparts adapted to slice and cut skin. Examples include midges and tabanids.

Mouthparts resembling hypodermic needles used for piercing and sucking blood. Seen in mosquitoes, stable flies, and sucking lice.

Mouthparts adapted for feeding on blood. They can be cutting, slashing, or piercing.

A long, forward-projecting structure used for piercing and sucking. Commonly found in blood-feeding insects like mosquitoes.

Mouthparts adapted for piercing skin and sucking blood. They have a proboscis for piercing and labella for sponging.

The evolution of specialized mouthparts in insects to effectively feed on different food sources, including blood.

House flies have sponging mouthparts adapted for absorbing liquid food, like secretions or blood. Their mouthparts are complex but designed for sponging and extend only during feeding.

Chelicerae are jaw-like appendages found in arthropods like ticks. They are used to pierce the host's skin, creating an entry point for the hypostome.

Some parasites, like fleas, have flattened bodies to move easily through dense fur or hair coats, allowing them to stay securely attached to their host.

Parasites may use hooks, combs, or scales on their bodies to help them cling firmly to their host, preventing them from being dislodged.

Some parasites, like Sarcoptes scabiei, have a large surface area to volume ratio, allowing them to survive for longer periods away from their host.

A type of pathogen transmission where the vector (carrier) doesn't play a role in the pathogen's life cycle, simply carrying it on its body.

A type of pathogen transmission where the vector is actively involved in the pathogen's life cycle, requiring the pathogen to multiply within the vector before transmission.

A type of biological transmission in ticks, where pathogens survive through multiple life stages (larvae, nymphs, adults) and can be transmitted by a single tick.

For some pathogens transmitted by ticks, they must move from the tick's gut to its salivary glands before they can be transmitted to a new host.

Some ticks require three different hosts throughout their life stages, with each stage feeding on a different host, allowing for efficient transmission of pathogens.

Understanding the life cycles of parasites, particularly the different stages they go through, helps in identifying infections and determining the best treatment strategies.

Arachnids, like ticks and mites, have four pairs of legs in both nymph and adult stages, a fused head and chest (cephalothorax), and no antennae.

Nits are the eggs of lice, specifically the human head louse, Pediculus humanis capitus. These eggs are cemented to hair shafts by the female louse.

Fleas, like the Spilopsyllus cuniculi that infects rabbits, have a complete metamorphosis with eggs, larvae, pupae, and adults. Females lay eggs continuously, and adults feed repeatedly on hosts.

Blood-sucking lice, like the human head louse, undergo partial metamorphosis. They lay eggs on hair shafts, and nymphs molt three times before becoming sexually mature adults.

Understanding insect life cycles helps us target control measures effectively. By knowing the different stages of a parasite's life cycle, we can design treatments to disrupt their development and spread.

A hard outer covering that protects arthropods from desiccation, pathogens, and predators.

The process of drying out due to loss of moisture.

A trait or characteristic that helps an organism survive and reproduce in its environment.

Understanding an arthropod's life cycle is crucial for managing infestations. Targeting vulnerable stages like eggs, larvae, or nymphs can be more effective than simply killing adults.

Ticks go through three stages: larva, nymph, and adult. Each stage requires a different host for feeding and development. This allows efficient transmission of pathogens, as the tick can spread disease across multiple hosts.

Arthropod parasites have developed strategies to survive harsh conditions, including entering a dormant state (like eggs or pupae), molting, or spending time hidden within the host.

Most arthropod parasites reproduce rapidly, taking advantage of favorable conditions. This results in large population increases, often leading to outbreaks or infestations.

These are transitional stages in an arthropod's life cycle where significant development occurs; they are often hidden within the previous stage's exoskeleton.

Myiasis fly larvae are parasitic and feed on living tissue, causing skin lesions and potential harm to the host.

Harvest mite larvae are parasitic, feeding on blood with their mouthparts. They're only parasitic in this stage, not as nymphs or adults.

Sheep blow fly larvae, or maggots, are parasitic and feed on living tissue, often causing serious skin damage and infections in sheep.

Many arthropods are only parasitic during specific stages of their life cycle, having different ways of feeding and surviving as larvae, nymphs, or adults.

Understanding different feeding adaptations and life cycle stages of arthropods is crucial for developing effective control methods.

Arthropods have evolved different mouthparts specialized for piercing, cutting, or sucking blood from their hosts, depending on their feeding habits.

Some parasites have thin bodies to move easily through dense fur or hair.

Hooks and combs on the parasite's body help it cling to its host.

Helps parasites survive for longer periods away from their host.

Pathogens in ticks must move from the gut to the salivary glands for transmission.

These are found at the end of the labium in insects, especially those with sponging mouthparts. The teeth help them rasp and pierce the skin during feeding.

This type of mouthpart acts like a sponge, absorbing secretions or liquids from mucous membranes or even blood. Examples include house flies, face flies, and horn flies.

These include sharp chelicerae that cut the skin, and a hypostome (like a tube) for sucking blood. Together, they form a barbed feeding tube.

This structure in ticks is a specialized part of their mouthparts that acts like a tube. It inserts into the host's skin after the chelicerae pierce it, allowing blood to be sucked up.

Ticks have special mouthparts - sharp chelicerae cut the skin, making way for the hypostome, a tube-like structure, to be inserted into the skin for blood feeding.

Parasites have special features to help them find, attach to, and feed from their hosts. These adaptations are key to their survival.

Fleas are highly adapted to find, attach to, and feed from their hosts. They have features like strong legs for jumping and sharp mouthparts for biting.

A small group of fungi capable of causing infections in healthy individuals, with only around 400 species out of 148,000 known fungi considered pathogenic.

Fungi that can switch their form between a single-celled yeast shape and a filamentous mold shape, depending on environmental conditions.

Fungal filaments (hyphae) that have cross-walls (septa) dividing them into cells, allowing for efficient transport and nutrient exchange.

Asexual spores produced by fungi, particularly molds, that are important for dissemination and identification.

A projection (germ tube) extending from a parent yeast cell, involved in the process of budding and reproduction.