leaf

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Fig. 205 Leaf. (a) Simple leaves. (b) Compound leaves.click for a larger image
Fig. 205 Leaf . (a) Simple leaves. (b) Compound leaves.

leaf

the principal photosynthetic organ of vascular plants, which typically consists of a flattened lamina joined to the stem by a stalk or petiole, at which junction an axillary bud can be found. There are numerous types of leaves.
  1. dorsiventral leaves are held horizontally with the upper half of the lamina containing the majority of photosynthetic cells (see MESOPHYLL for diagram). Typically, the lower epidermis contains the majority of STOMATA through which gas exchange and transpiration take place. Leaf veins are usually arranged in a ‘net’ venation with principal veins called midribs. The lamina can be indented to form a ‘compound’ leaf or remain as a simple structure. See Fig. 205 . Dorsiventral leaves are typical of DICOTYLEDONS.
  2. isobilateral leaves grow erectly, with a sword-like shape and are typical of MONOCOTYLEDONS. Both epidermal surfaces contain stomata with palisade mesophyll tissue packed underneath. Isobilateral leaves have a parallel venation and are not divided into compound structures. See also KRANZ ANATOMY.
  3. centric leaves are more or less cylindrical with a central region containing the vascular bundles surrounded by mesophyll tissue. Examples are the needles of pine trees, and onion leaves.

Some leaves have special modifications. For example, water storage leaves are found in many plants living in dry conditions (e.g. cacti). In other plants the leaves are modified into tendrils for climbing (e.g. pea) while in some the leaves have become spines, e.g. gorse.

leaf

terminal outgrowths of plant foliage, usually flat green blades that conduct the plants' photosynthesis. Of the foliage it is much the most nutritious part and is often incorporated into special feeds, e.g. lucerne leaf meal.

leaf intestinal impaction
impaction of the cecum and colon in horses with access to indigestible tree leaves.
leaf mustard
brassicajuncea.

Patient discussion about leaf

Q. What happens if you leave appendicitis alone? I have symptoms of appendicitis, but I don't want to go to the hospital. What should I do? and what could happen?

A. If you have symptoms of appendicitis you should see a doctor immediately, because the major complication of an untreated appendix is rupture and infection of the entire abdomen, that can lead to generalized sepsis.

Q. Any ideas about why she leaves some food in her plate. Thank you for your visit. My daughter is 8 years old and she is a poor eater. She never wants to eat dinner even if it's her favorite dish. And then she picks it and an hour later she says that she feels hungry. She never completes her plate, always leaving a bit, no matter what we feed her. Should she be forced to eat dinner and if she doesn't, have only the dinner to eat later? Any ideas about why she leaves some food in her plate?

A. She trusts her mom. The most common reason to be like this is she knows that she will get something to eat later from her dear mom. While she shouldn't be forced to eat, she should learn that her main meal in the evening will be served at the dinner time.
Some other things that you might do to help deal with your picky eater include:
• Make sure that she isn't eating a big snack after school or filling up on juice, soda, or even milk before dinner.
• Offer her smaller portions so that there isn't as much left over on her plate.
• Don’t offer bribes or rewards for eating.
• Never talk about dieting, calories, and such, especially if she or other family members have problems with being overweight. Instead, talk about eating healthy.
• Consider not offering her anything else to eat if she misses dinner or just offer a small, healthy snack.

Mainly a visit to your Pediatrician to monitor her growth, development and eating habits would also be a good idea. Hug her now!

Q. What makes me worried that it’s really painful but might not be able to leave all of a sudden. Doctor diagnosed my son with peanut allergy after some tests. His body generates rashes and these eruptions are painful for him. I thought it big to be eczema as I heard about it, but now it is diagnosed and I am not able to decide how to avoid him of not giving peanuts and to keep him away as he likes them. Once near to me I can try to avoid to some extent, but once away to school or in playing with friends he does eat them regularly. What makes me worried that it’s really painful but might not be able to leave all of a sudden.

A. My friend’s brother does have the experience of peanut allergy. These peanuts are nutritious, but its allergy is awful. He has a clear understanding of this and avoids eating them. I too have found that he followed strict guidelines for not eating them when it was diagnosed for him. The best thing is to create some other or new foodstuff taste for him which might help him be consumed an alternative for nuts for some times and then provide with peanuts for him to regain his remembrances for the culprit he consumes. It needs to be done under your care for long time till he develops the inhibitions for nuts. You must also remember to memorize some medicine names and symptoms, so, if consumed unknowingly can explain what it is to anyone responsible nearby.

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References in periodicals archive ?
Present study indicates that the time taken from emergence to true leaves was not significantly affected by N application which indicates that nitrogen application seemed to be sufficient at the early growth stages and later on nitrogen effects on other developmental stages (Uhart and Andrade 1995).
cinerea during the first pair of cotyledonary leaves stage (T1) and the first pair of true leaves stage (T2) are shown in Figure 3.
In other words, the opening of the True Leaves charter school provided me with an opportunity to document the initial "touch" of the plane's wheels on to the runway of implementation--that moment in time when theory meets practice and when new ideas begin to take shape.
Since V(P') does not contain any true leaf, the set of true leaves of V LR(t) is exactly the union of true leaves of the complete binary trees {left([v.
This herbivory treatment was applied 4 and 21 days after planting into a plastic pot to simulate the extent of cotyledon removal by herbivores before and after the emergence of the first set of true leaves.
Some species display both types of leaves in their lifetime: phyllodes in their youth and pinnately compound true leaves in their adulthood.
Watch for the second set of true leaves before transplanting.
Kerby and Keely (1987) also found that manual removal of the first two true leaves had no significant effect on early plant growth.
Two indices of early seedling shoot growth were used: presence or absence of true (adult) leaves by the end of the first summer and, for seedlings producing true leaves, the maximum length of the largest one.
Like all members of the cactus family, the saguaro does not have true leaves.
Working with seedlings that had just produced their first set of true leaves, the scientists showered the plants with acid rain for one hour, then examined the plants two days later for leaf damage.
When true leaves are visible, we prick out into modules or big seed trays, then pot on until there is no danger of frost.