C
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Tiny, thin-walled blood vessels found in most tissues, allowing exchanges of gases, nutrients, and waste products between the tissue cells and the blood.
Important biological molecules that include sugars and starch. Carbohydrates - especially glucose - provide energy and also have structural roles in and around cells.
A gas composed of one carbon atom and two oxygen atoms, often abbreviated as CO2. Carbon dioxide is formed in the body's tissues as a waste product of aerobic cellular metabolism, and is carried away from the tissues by the blood. Excess carbon dioxide is disposed of via the lungs and airways when we breathe out.
Threadlike structures in the nucleus of a cell. Each chromosome is composed of a long DNA molecule supported by - and wrapped around - special proteins called histones. Most human cells contain 46 chromosomes. The exceptions are cells with no nuclei, such as red blood cells, and cells being prepared as gametes (eggs and sperm) which eventually contain only 23 chromosomes. Chromosomes become most clearly visible during cell division, when they become tightly coiled and compacted (micrograph).
A disease or process that lingers and lasts.
Microscopic hair-like processes of some cells: they are capable of active beating movements producing movement of fluids in contact with them. Ciliated epithelia line most of the airways, for example.
The developing baby before birth, especially during the early stages of development soon after fertilisation.
This is a hard word to define! It is something we all have, but none of us really know what it is. It has something to do with an awareness of self. There is currently a renewed discussion about the nature of consciousness - whether it is an emergent property of brain activities or whether it is the product of something outside the material realm studied and described by science.