Cells (4) Flashcards
How are cells formed?
> Human body develops from single cell calles zygote, resulting from joining of ovum and sperm
Cell division follows (mostly in first 12 weeks) and cell specialisation as foetus grows- these cells hav the same genetic makeup as the zygote
What is a cell?
> Building blocks of the body
Over 200 types in the body
Most are microscopic (10-30um diameter)
What is the largest cell?
Ovum
500um and just visible to naked eye
What is the smallest cell?
Erythrocyte
7.5um
What is the longest cell?
Neurone
Up to 1m in length but microscopically thin- longest is sciatic nerve
What cells connect body parts?
Fibroplasts
What cells form linings?
Erythrocytes
What cells transport gases?
Erythrocytes
What cells move organs and body parts?
Skeletal muscle cells and smooth muscle cells
What cells gather information and control body functions?
Nerve cell
What cells store nutrients?
Fat cells
What cells fight disease?
Macrophages
What cells are involved in reproduction?
Ovum and sperm
What is cell theory?
> The cell is the basic structural and functional unit of life
Activity of an organism depends on individual and collective activity of its cells
Biochemical and metabolic activities of cells are dictated by its subcellular structure
Continuity of life has a cellular basis
What elements are all cells composed of?
Carbon, hydrogen, nitrogen and oxygen
Have trace amounts of other elements