10.2.1: The -enchymas
- Page ID
- 37211
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\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)There are three major cell types in plants that we can distinguish by differences in their cell walls. These three cell types are parenchyma, collenchyma, and sclerenchyma.
![The three different cell types found in plants](https://bio.libretexts.org/@api/deki/files/26937/Cell_Types_Updated.png?revision=1&size=bestfit&width=576&height=729)
Parenchyma
Parenchyma cells are characterized by an even, relatively thin primary wall.
![Many cells tightly packed together with thin cell walls. The cells contain round structures.](https://bio.libretexts.org/@api/deki/files/44718/2560px-Cortex_Parenchyma_in_Herbaceous_Dicot_Ranunculus_(34758991731).jpg?revision=1&size=bestfit&width=787&height=443)
Collenchyma
Collenchyma cells are characterized by an uneven, relatively thick primary wall.
![A cross section through a peppermint stem showing a region of small cells with angular cell walls that are unevenly thickened.](https://bio.libretexts.org/@api/deki/files/29997/Inked1920px-Mentha_angular_collenchyma_LI.jpg?revision=1&size=bestfit&width=480&height=358)
![A cross section through tissue that looks like a checkerboard of cell wall and cytoplasm. This is collenchyma tissue.](https://bio.libretexts.org/@api/deki/files/44719/Collenchima.jpg?revision=1&size=bestfit&width=473&height=355)
Sclerenchyma
Sclerenchyma cells are characterized by the formation of a secondary wall composed of lignin. This secondary wall forms within the primary wall and eventually leads to the death of the cell. Sclerenchyma cells are dead at functional maturity.
![A dense cluster of cells with evenly thick cell walls that have stained dark red](https://bio.libretexts.org/@api/deki/files/44720/Plant_cell_type_sclerenchyma_fibers.png?revision=1)
![Cross section of a fiber cell](https://bio.libretexts.org/@api/deki/files/44724/Cross_section_of_a_fiber_cell.jpg?revision=1&size=bestfit&width=516&height=385)
![Three large clusters of sclereids in pear cortex](https://bio.libretexts.org/@api/deki/files/44722/2560px-Sclereids_in_Pyrus_pear_(36452689110).jpg?revision=1&size=bestfit&width=603&height=340)
![A single sclereid, unstained, in pear cortex](https://bio.libretexts.org/@api/deki/files/44723/Plant_cell_type_sclerenchyma_sclereid.png?revision=1)