Microorganisms and Cell Biology Vocabulary

Vocabulary terms covering cellular biology and the roles of microorganisms in food, environment, and nitrogen fixation.

Nerve cells

Shaped very long with branched extensions to carry messages across the body and reach distant organs.

Fermentation

The process where microorganisms break down sugars into simpler substances, releasing gases and alcohol, making food soft and fluffy.

Yeast

A fungus known as 'the baker's friend' that feeds on sugar in dough and releases $CO_2$, causing the dough to rise and become spongy.

Lactobacillus

Bacteria that converts milk sugar (lactose) into lactic acid to form curd.

Manure

A natural substance obtained by the decomposition of animal waste and plant residues which increases soil fertility and provides essential nutrients.

Bio-gas

A fuel produced by some bacteria in oxygen-free conditions, used for cooking, heating, electricity, and vehicles.

Spirulina

A microalgae that provides $B12$ supplements and is used in cleaning water and making bio fuel.

Rhizobium

Bacteria found in the root nodules of legumes that fixes nitrogen by converting it into nitrates and nitrites.

Microalgae

Microscopic plant-like organisms that use sunlight to make food and produce more than half of Earth's oxygen supply.

Unicellular Organisms

Organisms made of one cell that lack some organelles and have an undefined nucleus without a nuclear membrane.

Multi-cellular Organisms

Organisms made of many cells with all organelles present and a well-defined nucleus with a nuclear membrane.

Robert Hooke

The scientist who first observed cork cells and introduced the term 'cell'.

Antonie van Leeuwenhoek

The scientist known as the 'father of microbiology' who first observed living microorganisms.

Cell membrane

Part of the cell that protects the internal environment and regulates the movement of nutrients and wastes.

Cell

The basic unit of life and the smallest structure that can carry out all necessary functions like respiration, growth, and reproduction.

Cell wall

A structure in plant cells that provides shape, strength, support, and protection against bursting due to transpiration.

Muscle cells

Cells that are spindle-shaped and used for movement.

Levels of Organization

$$\text{Cell} \rightarrow \text{Tissue} \rightarrow \text{Organ} \rightarrow \text{Organ System} \rightarrow \text{Organism}$$

Denitrifying bacteria

Bacteria that convert nitrates back into atmospheric nitrogen ($N_2$).

Ammonia

A natural fertilizer formed during the nitrogen fixation process.