Human Biology: Cells and Their Functions

This set of flashcards covers key concepts and terminology from the lecture on human biology, specifically focusing on cells, their structure, and functions.

Cell Theory

The scientific theory that states all living things are composed of cells, cells are the basic units of structure and function in organisms, and new cells arise from existing cells.

Plasma Membrane

A selectively permeable membrane that surrounds the cell, controlling what enters and leaves the cell.

Cytoplasm

The semi-fluid substance within the plasma membrane that contains organelles and is the site of metabolic processes.

Mitosis

The process of cell division that results in two identical daughter cells with the same number of chromosomes as the parent cell.

Meiosis

A type of cell division that reduces the chromosome number by half, resulting in four genetically diverse gametes.

Homeostasis

The maintenance of stable internal conditions in an organism despite changes in external environments.

Lysosome

An organelle that contains digestive enzymes to break down waste materials, old cell parts, and foreign substances.

Mitochondria

Organelles known as the powerhouses of the cell, responsible for producing ATP through cellular respiration.

Endocytosis

The process by which cells take in large molecules or particles by engulfing them in a vesicle.

Exocytosis

The process by which cells expel materials in vesicles that fuse with the plasma membrane.

Hypotonic Solution

A solution that has a lower concentration of solutes than the inside of a cell, causing the cell to swell.

Hypertonic Solution

A solution that has a higher concentration of solutes than the inside of a cell, causing the cell to shrink.

Apoptosis

Programmed cell death that occurs in multicellular organisms, important for eliminating damaged or unnecessary cells.

Cancer

A group of diseases characterized by uncontrolled cell division, which can lead to the formation of tumors.

Phagocytosis

A type of endocytosis where the cell engulfs large particles, such as bacteria or cellular debris.

Pinocytosis

A type of endocytosis known as