The phrase "apex of stem" is correct and usable in written English.
It can be used in contexts related to botany, biology, or any field discussing structures where "apex" refers to the top or highest point of a stem.
Example: "The apex of the stem is crucial for the growth and development of the plant."
Alternatives: "tip of the stem" or "top of the stem".
Both grain sorghum BTx623 and sweet sorghum Rio were grown until anthesis and total RNA from internode 8 for each genotype (internodes were numbered from the base towards the apex of the stem) was extracted using the RNeasy Plant Mini Kit (QIAGEN Inc., USA).
The apex of the stem is pallid, and the whitish base covered with coarse, stiff hairs.
In dichotomous branching, the branches form as a result of an equal division of a terminal bud (i.e., a bud formed at the apex of a stem) into two equal branches that are not derived from axillary buds, although axillary buds are present elsewhere on the plant body.
The apex of the stem extends into the gleba to form a columella that reaches the top of the cap.
Caulocystidia are abundant on the apex of the stem; they are club-shaped to cylindrical, thin-walled, hyaline, and measure 3 9 µm wide.
The variety amarus is similar in appearance, but has bitter-tasting flesh, while variety dubius has a lighter colored-cap and less distinctive reticulations on the apex of the stem.
Our investigations indicated that any spine and any part of the spine could be used, but fresh spines found at the apex of growing stems produced the highest DNA yields.
Flowers are produced in large numbers on inflorescences that arise from the apex of the main stem.
The arrowheads highlight the strongest accumulation of GFP-KCBP at the apex of the main stem and the apical region of the incipient primary branch.
As reported by Jeudy and Munier-Jolain (2005), the development of branches is increased in winter pea cultivars because of the frost damage experienced on the apex of the main stem.
