Biology 12 - Unit 2 - Cell structure and Function vocabulary

10. Cell wall

A membrane of the cell that forms external to the cell membrane whose main role is to give cells rigidity, strength and protection.

6. Fluid mosaic model

A model conceived by S.J. Singer and Garth Nicolson in 1972 to describe the structural features of biological membranes.

15. Smooth endoplasmic reticulum

A part of endoplasmic reticulum that is tubular in form and lacks ribosomes.

12. Nuclear pores

Any of the many perforations on the nucleus as a result of the assembly of nucleoporins that span the nuclear envelope.

22. Chloroplast

Chlorophyll-containing plastid found within the cells of plants and other photosynthetic eukaryotes

4. Organelles

Literally, the term means "little organs". As the body is composed of various organs, the cell, too, has "little organs" that perform special functions. They are membrane-bound compartments or structures of a cell.

8. Hydrophilic head

The hydrophilic heads are on the outer part of the bilayer because they are "water loving".

3. Nucleus

The large, membrane-bounded organelle that contains the genetic material, in the form of multiple linear DNA molecules organized into structures called chromosomes

2. Cell membrane

The outer covering of the cell consisting of a lipid bilayer with proteins embedded in it.

1. Cell theory

The scientific theory describing cells, e.g. the cell as the basic unit of living organisms, and that all cells arise only from pre-existing, living cells

18. Lysosomes

a cell organelle containing enzymes that digest particles and that disintegrate the cell after its death.

9. Selectively permeable

a function of the plasma membrane that is essential to maintain homeostasis by regulating the passage of some substances while preventing others from entering the cell

26. Flagella

a long, lashlike appendage serving as an organ of locomotion in protozoa, sperm cells, etc.

13. Endoplasmic reticulum

a network of tubular membranes within the cytoplasm of the cell, occurring either with a smooth surface or studded with ribosomes involved in the transport of materials.

7. Hydrophobic tail

a part of the main component of the cell membrane i.e, a phospholipid that consists of a sugar , phosphate and two fatty acid chains (lipids)

17. Ribosomes

a tiny, somewhat mitten-shaped organelle occurring in great numbers in the cell cytoplasm either freely, in small clusters, or attached to the outer surfaces of endoplasmic reticula.

21. Mitochondria

an organelle in the cytoplasm of cells that functions in energy production.

16. Golgi apparatus

an organelle, consisting of layers of flattened sacs, that takes up and processes secretory and synthetic products from the endoplasmic reticulum.

14. Chromosomes

any of several threadlike bodies, consisting of chromatin, that carry the genes in a linear order.

25. Cilia

minute hairlike organelles, identical in structure to flagella, that line the surfaces of certain cells and beat in rhythmic waves, providing locomotion to ciliate protozoans.

24. Cytoskeleton

shifting lattice arrangement of structural and contractile components distributed throughout the cell cytoplasm, functioning as a structural support and transport mechanism.

23. Centrioles

small, cylindrical cell organelle, seen near the nucleus in the cytoplasm of most eukaryotic cells, that divides in perpendicular fashion during mitosis.

5. Cytoplasm

the cell substance between the cell membrane and the nucleus, containing the cytosol, organelles, cytoskeleton, and various particles.

11. Nuclear envelope

the double membrane surrounding the nucleus within a cell.

19. Phagocytosis

the ingestion of a smaller cell or cell fragment, a microorganism, or foreign particles, formation of a vacuole: characteristic of amebas and some types of white blood cells.

20. Pinocytosis

the transport of fluid into a cell by means of local infoldings by the cell membrane so that a tiny vesicle or sac forms around each droplet, which is then taken into the interior of the cytoplasm.