Cell Structure and Function

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Cell Noun

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[sel]

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Cell

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The basic structural and functional unit of all living things, containing organelles that work together to keep it functioning.

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Example: This diagram shows a cross-section of an animal cell, labeling its main parts, called organelles, which work together to keep the cell alive.

Front

Organelle Noun

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[or-guh-nel]

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Organelle

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A specialized structure found within a living cell, where each has a specific job or function to perform.

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Example: This image shows a mitochondrion, which is an example of an organelle. Organelles are specialized structures inside a cell that perform specific jobs.

Front

Nucleus Noun

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[noo-klee-uhs]

Back

Nucleus

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The large, membrane-bound organelle that contains the cell's genetic material and controls its growth and reproduction activities.

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Example: This diagram shows a cutaway view of the cell's nucleus, labeling its main parts like the nucleolus, chromatin, and the protective nuclear envelope.

Front

Cytoplasm Noun

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[sahy-tuh-plaz-uhm]

Back

Cytoplasm

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The jelly-like substance filling the cell, which surrounds the nucleus and holds all of the organelles in place.

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Example: This diagram shows cytoplasm as the jelly-like substance that fills the cell, located between the nucleus and the outer cell membrane.

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DNA (Deoxyribonucleic acid) Noun

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[dee-ok-see-rahy-boh-noo-klee-ik as-id]

Back

DNA (Deoxyribonucleic acid)

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A self-replicating molecule carrying the genetic instructions for the development, functioning, growth, and reproduction of all known organisms.

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Example: This diagram shows that DNA is a double helix molecule made of a sugar-phosphate backbone and specific pairs of bases: Adenine (A) with Thymine (T), and Guanine (G) with Cytosine (C).

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Nuclear Membrane Noun

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[noo-klee-er mem-breyn]

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Nuclear Membrane

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The double-layered membrane enclosing the nucleus, regulating passage of materials between the nucleus and the cytoplasm.

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Example: This diagram shows the nuclear envelope (or membrane) which acts as the outer boundary of the nucleus, containing the cell's genetic material.

Front

Chromosome Noun

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[kroh-muh-sohm]

Back

Chromosome

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A thread-like structure of nucleic acids and protein found in the nucleus, carrying genetic information in the form of genes.

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Example: This diagram shows that a chromosome is a structure found inside a cell's nucleus and is made of tightly coiled DNA carrying genes.

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Nucleolus Noun

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[noo-klee-oh-luhs]

Back

Nucleolus

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A small, dense spherical structure in the nucleus of a cell during interphase, responsible for ribosome synthesis.

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Example: This diagram shows the nucleolus, a dense structure located inside the cell's nucleus, surrounded by chromatin and the nuclear membrane.

Front

Ribosome Noun

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[rahy-buh-sohm]

Back

Ribosome

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A minute particle consisting of RNA and associated proteins, found in large numbers and functioning as the site of protein synthesis.

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Example: This diagram shows a ribosome reading instructions from an mRNA strand to build a protein by linking amino acids together into a growing chain.

Front

Endoplasmic Reticulum (ER) Noun

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[en-doh-plaz-mik ri-tik-yuh-luhm]

Back

Endoplasmic Reticulum (ER)

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A network of membranous tubules within the cytoplasm, involved in protein and lipid synthesis and transport.

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Example: This diagram shows the rough endoplasmic reticulum, a network of membranes inside a cell, studded with small dots called ribosomes which give it a 'rough' appearance.