How Do Seeds Germinate? Monocots vs. Dicots

Updated on February 20, 2017
A comparison of the early growth of beans (dicot) versus corn (monocot).
A comparison of the early growth of beans (dicot) versus corn (monocot). | Source

What is the Difference Between Monocots and Dicots?

As you undoubtedly know, flowering plants are frequently separated into two different classes: the dicots and monocots. Apart from some superficial differences, such as in leaf venation and floral arrangement, the primary distinction between these two groups lies within their seed structure. All seeds have a certain number of cotyledons, or seed leaves, which end up serving a variety of functions depending on the plant species. All angiosperms have either one or two of these cotyledons (hence the terms monocot and dicot) and this difference ends up playing a big role in how the process of seed germination plays out.

First, however, I will give a brief overview of the parts of a seed and seed germination in the most general sense.

A diagram of an avocado seed.  The avocado is a dicot since it has two cotyledons.
A diagram of an avocado seed. The avocado is a dicot since it has two cotyledons. | Source

A Brief Overview of Seed Structure and Germination

As a whole seeds basically have two main parts: the embryo and everything else. Of all of these parts, the embryo is the most important as it is what will later develop into the mature plant. The rest of the seed serves to protect and nourish this embryo.

In angiosperms, the embryo has three main parts: the hypocotyl, the radical, and the cotyledon(s). The hypocotyl contains the apical meristem, so it is from this point where the above-ground stem grows from. The radical is at the base of the seed and it develops into the plant's roots. The cotyledons, like I mentioned earlier, perform different functions depending on the plant type.

Diagram of a wheat seed (a monocot).
Diagram of a wheat seed (a monocot). | Source

The Difference

So, the main difference between these two types of seeds is the purpose of the cotyledons.

Dicots

In dicotyledonous plants, the cotyledons are well developed and absorb and store nutritive tissue from the endosperm of the seed. These two cotyledons are then often pushed up out of the soil (as shown in the picture of the beans at the top of this page) and serve as the plants first vegetative "leaves." This does not occur in all dicots, however. In others the cotyledons remain underground and merely provide nutrition for the growing meristems.

Monocots

In monocots, the seed's endosperm is often much larger (as evident in the diagram of a wheat seed on the right) than that of the dicots. In this case, the single cotyledon stays below ground and within the seed where it digests the endosperm and transfers the stored energy to the developing embryo. Additionally, in monocots the radical portion of the embryo is aborted and only fibrous, adventitious roots are produced.

How to Spot the Difference

The best way to differentiate between monocots and dicots is to perform a seed dissection and observe the growth process of a germinated seed. If this isn't feasible, the next best thing to do is to observe some of the characteristics of a mature specimen. Monocots typically have their floral parts in numbers that are divisible by 3 (ie. 3 sepals, 3 or 6 petals, 6 stamens, etc.) and dicots have their parts generally in groups of 4,5, or more. Additionally, monocot leaves usually have parallel venation, while dicot leaves are generally more reticulated. Of course, these are guidelines rather rules and there are always exceptions!

Questions & Answers

    Comments

      0 of 8192 characters used
      Post Comment

      • profile image

        elizabeth 

        5 years ago

        hello thank you

      • lumberjack profile imageAUTHOR

        lumberjack 

        6 years ago

        Thanks! :)

      • WD Curry 111 profile image

        WD Curry 111 

        6 years ago from Space Coast

        Great hub . . . informative and attractive. Yeah, I knew this and I grow a lot of plants. However, I had forgotten most of the "official" details that you so aptly covered. I am bookmarking this for my kids. What a great science fair project!

      working

      This website uses cookies

      As a user in the EEA, your approval is needed on a few things. To provide a better website experience, owlcation.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

      For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: https://owlcation.com/privacy-policy#gdpr

      Show Details
      Necessary
      HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
      LoginThis is necessary to sign in to the HubPages Service.
      Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
      AkismetThis is used to detect comment spam. (Privacy Policy)
      HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
      HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
      Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
      CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
      Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
      Features
      Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
      Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
      Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
      Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
      Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
      VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
      PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
      Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
      MavenThis supports the Maven widget and search functionality. (Privacy Policy)
      Marketing
      Google AdSenseThis is an ad network. (Privacy Policy)
      Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
      Index ExchangeThis is an ad network. (Privacy Policy)
      SovrnThis is an ad network. (Privacy Policy)
      Facebook AdsThis is an ad network. (Privacy Policy)
      Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
      AppNexusThis is an ad network. (Privacy Policy)
      OpenxThis is an ad network. (Privacy Policy)
      Rubicon ProjectThis is an ad network. (Privacy Policy)
      TripleLiftThis is an ad network. (Privacy Policy)
      Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
      Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
      Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
      Statistics
      Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
      ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
      Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)