Stem is a long and large stalk which is the main body that serves as the support to vegetative and reproductive shoots. In addition, it is where the leaves grow and the primary root is connected. Moreover, the stem is part of shoot system of a plant. Parts of the stem: Apical bud - also known as terminal bud which is located at the tip of the plant where the shoot growth occurs. Leaf - is a thin, flattened and usually green organ where the photosynthesis happens. Petiole - the stalk that joins a leaf to a stem. Node - is a point of attachment of a leaf. Internode - a space between two nodes. Axillary bud - a bud that grows at the axil of the leaf and is capable of developing into a branch shoot or flower cluster. Characteristics of stems: Stem develops from pumule and epicotyl of the embryo and it grows ascendingly and aerially of the plant axis. Stem is generally negatively geotropic which grows upward and positively phototropic which grows downward. Stem consist of terminal bud where shoot growth occurs, nodes where the leaf is attached to and grows, and internodes which is the space between two nodes. Young stem is green and performs photosynthesis. When stem is matured, flowers and fruits starts to develop on it. Functions of stems: Provides support to the plant and bear leaves, buds, flowers, and fruits. Serves as a transportation of water and other minerals from roots to the rest of the parts of a plant. Some of the stems conduct photosynthesis and stores water such as cactus. The stem allows the leaves to arrange in a way that they are able to receive direct sunlight in order to efficiently perform photosynthesis and allow gas exchange. Some stems are modified to carry out vegetative propagation which is a form of asexual reproduction seen in plants. Forms of stems: Aerial Stem - is a stem that grows vertically above the ground. Erect Stem - is a stem that can stand upright without any support and grows above the ground. Weak Stem - is a thin, soft, and weak stem that can't stand upright and therefore needs support. There are four types of weak stem namely climbers, twiner, trailers, and creepers. Reduced Stem - is a stem that is being extremely reduced in bulbs. Underground Modified Stem - is a stem that is being modified to for storage of food and it grows underground.

Photosynthesis is the process of which the plant produces its own food by absorbing light energy from sunlight and converts it into chemical energy in the form of ATP and NADPH to form glucose which then stored in their bodies as carbohydrates. It is essential for it absorbs carbon dioxide which is harmful for humans and animals. Additionally, it releases oxygen as a byproduct by the process of splitting water which is called Photolysis. Moreover, it starts the ecological food web due to the fact that it produces glucose which serves as the energy for heterotrophs when they consume it. 2 Phases of Photosynthesis: - Photosynthesis has two phases which are the light-dependent reaction and the light-independent reaction that takes place in the chloroplast. Phase 1: Light-dependent reaction This is the first step in photosynthesis and is also known as Light Reaction by which it requires light energy from sunlight. The light energy is being absorbed by chlorophyll and converts it into chemical energy as the byproduct of this reaction. Those chemical energies are ATP and NADPH. Also, oxygen is a byproduct of this reaction for it was released during the water splitting process of Light Reaction which is called the Photolysis. Phase 2: Light-independent reaction This is the second step of photosynthesis and is also known as Dark Reaction or Calvin Cycle by which it doesn't requires light energy due to the fact that it uses ATP and NADPH which came from the Light Reaction as a fuel for this process to work. Additionally, this reaction requires carbon dioxide and hydrogen in order to make glucose as a byproduct.

Leaves are thin, flattened and usually green organ that grows at the stem of the plant. It is an essential part of shoot system for it is where the photosynthesis takes place and produces glucose as food for the plant. Main parts of the leaf: - The main parts of the leaf is consist of three parts namely leaf base, petiole, and lamina. Leaf base - is the slightly expanded area where the leaf attaches to the stem and it contains two small leaf-like structure called stipules. Petiole - is a stalk that attaches the leaf base to the stem. Lamina - is also known as leaf blade. It is a flat surface of the leaf that contains midrib and veins. In addition, it is known as the photosynthetic surface of the plant. Venation: - It is the arrangement of veins and veinlets that can be found at the leaf blade or lamina. Reticulate venation - are described as net-like veins because the arrangement of veins are scattered randomly. Parallel venation - are described as parallel-like veins by which the arrangement of veins are parallel to each other. Types of leaves: - There are two broad categories of leaves and those are the simple and compound leaves. Simple leaf - is when only one lamina is connected to the main stem by a petiole. Compound leaf - is composed of two or more leaflets on one stalk. Types of compound leaf: - The compound leaf is further divided into two sub-categories which are the palmately and pinnately compound leaves. Palmately compound leaf - is a leaf whose leaflets are attached at the tip of petiole. Pinnately compound leaf - is a leaf whose midribs are divided into numerous leaflets and connects to one axis. Phyllotaxy: - It is the arrangement of leaves in the stem. Alternate - is when one leaf develops at each node alternatively. Opposite - is when a pair of leaves develops opposite to each other. Whorled - is when two or more leaves develops at one common node. Modification of Leaves: - Leaves are modified in order to survive within its own environment. Each of the modification has its own function such as protecting itself, storage of food, support, and etc. Storage leaves - thick and succulent leaves that stores water. Leaf tendrils - it is a thread-like structure that found at the tip of the leaf. Scale leaves - thin, membranous structures, without stalks, brownish or colourless in appearance. Phyllode - petiole becomes flattened, taking the shape of a leaf and turns green. Insectivorous leaves - the leaf is modified to catch and digest insects. Functions of leaves: - leaves performs different functions in order to help the plant live and survive and those are photosynthesis, transpiration, guttation, and storage. Photosynthesis - is where the light energy from sunlight absorbs and converts it into chemical energy that produces glucose as byproduct. Also, this process is where the oxygen is released and the carbon dioxide is absorbed. Transpiration - is a process where the stromata is opened to remove excess water from the plant. Guttation - is contradictory to transpiration by which the stromata is closed to remove excess water from the xylem at the edges of the leaf. Storage - leaves store water and nutrients for photosynthesis to happen.

Most of the plant cells are divided by Mitosis. Mitosis is a part of cell cycle in which a single cell divides and produces two daughter cells with identical chromosomal content of parent cell. Stages of Cell Division in Plants Interphase - This is where the cell grows, replicates its DNA and prepares for Mitosis. Prophase - In this phase, the chromatin starts to condense and the nucleolus will disappear  Metaphase - The spindle is attached to the chromosomes and the chromosomes are aligned at the center. Anaphase - The spindle starts to pull sister chromatids apart to the opposite ends of the cell. Telophase - The chromatids are already at the opposite ends of the cell and it starts to decondense. The spindle disappears. Cytokinesis - This is the last stage of Mitosis. This is where the cell divides into two daughter cells and forms cleavage furrows that splits the cell.

Central Dogma of Molecular Biology DNA to DNA = Replication DNA to RNA = Transcription RNA to Protein = Translation All about RNA: Composed of 4 nucleotides and 5 carbon sugar, phosphate. Thymine is replaced with Uracil and still pairs with Adenine The 5 carbon sugar has an extra oxygen Is single stranded Summarized steps of protein synthesis: Protein synthesis is the process in which cells make proteins. It occurs in two stages: transcription and translation. Transcription is the transfer of genetic instructions in DNA to mRNA in the nucleus. After the mRNA is processed, it carries the instructions to a ribosome in the cytoplasm. Translation occurs at the ribosome, which consists of rRNA and proteins. In translation, the instructions in mRNA are read, and tRNA brings the correct sequence of amino acids to the ribosome. Then rRNA helps bonds form between the amino acids, producing a polypeptide chain. It includes the steps of initiation, elongation, and termination. After a polypeptide chain is synthesized, it may undergo additional processing to form the finished protein. .

All about DNA: Located at the nucleus It is composed of 4 nucleotide bases namely, Adenine, Thymine, Guanine, and Cytosine and 5 carbon sugar and phosphate. It consist of 2 base pairing, Adenine pairs with Thymine and Guanine pairs with Cytosine. These 2 base pairs form a ladder like structure with edges at the side called the sugar-phosphate backbone. It is a double helix and is anti-parallel Steps in DNA replication: Hydrogen bonds break due to unwinding and separating of molecules. The new(daughter) strand pairs with the old(parental) strand. Thus, a new base pair is formed. Winding will occur as new nucleotides joined together by DNA Polymerase and resulting to a double helix.

Plant cells are the basic unit of life in plants and it is an eukaryotic cell in which it has membrane-bound nucleus. The major function of plant cells is the photosynthesis which takes place at the chloroplast that prepares food for the plant in order for it to survive on it's own because plants are autotroph for it produces its own food. Additionally, plant cells also stores nutrients needed for the growth and survival of plant. Moreover, it contains many organelles with specific functions. Below is a picture of a plant cell with parts and labels: