Blood cells & Hemostasis
What blood cell carries oxygen using hemoglobin?
Erythrocyte (RBC)
What term describes the body's ability to maintain a stable internal environment?
Homeostasis
What is another name for a white blood cell?
Leukocyte
What is the body's first physical barrier against pathogens?
Skin and mucous membranes
What two major lymphocytes are responsible for adaptive immunity?
B cells and T cells
What are the small cell fragments that help form a platelet plug?
Platelets (thrombocytes)
What is the normal blood pH range?
7.35–7.45
What structures filter lymph and contain immune cells that help detect pathogens?
Lymph nodes
What process allows cells like neutrophils and macrophages to engulf pathogens?
Phagocytosis
Which lymphocyte can differentiate into plasma cells that produce antibodies?
What is the overall process that stops bleeding after a blood vessel is damaged?
Hemostasis
What type of feedback mechanism reverses a change to return the body toward normal
Negative feedback
Which leukocyte is usually the first major phagocyte to respond to a bacterial infection?
Neutrophil
What four classic signs commonly occur during inflammation?
Redness, heat, swelling, and pain
What type of T cell directly destroys infected or abnormal body cells?
Cytotoxic T cell
What protein forms a mesh that strengthens and stabilizes a blood clot?
Fibrin
If body temperature rises, what response helps cool the body?
Sweating and vasodilation
Which leukocyte can leave the bloodstream and develop into a macrophage in tissues?
Monocyte
What innate immune cells recognize and kill virus-infected or abnormal cells without prior exposure?
Natural killer (NK) cells
What cells remain after an infection and allow the body to respond faster during a second exposure?
Memory B and T cells
During thrombolysis, what enzyme breaks down fibrin and dissolves the clot?
Plasmin
Blood glucose rises after eating. Which hormone lowers it by promoting glucose uptake and storage?
Insulin
Which organ filters the blood, removes old RBCs, and participates in immune responses?
Spleen
A pathogen enters the body through a cut in the skin. Which immune cells engulf the pathogen and destroy it using phagocytosis?
Macrophages
A person is exposed to the same pathogen years later and produces a faster, stronger immune response. What feature of adaptive immunity explains this?
Immunological memory