Plant Physiology: Internal Functions

• Botany is the scientific study of plants, including their physiology, structure, genetics, ecology, distribution, classification, and economic importance.

Plant Physiology

• Plant physiology explores the internal functions and processes of plants.
• Topics include photosynthesis, respiration, plant nutrition, hormone functions, tropisms, and nastic movements.
• Photosynthesis is the process by which plants convert light energy into chemical energy in the form of sugars.
• Respiration is the process of plants consuming stored sugars to produce energy for growth and other metabolic processes.
• Plant hormones, such as auxins, gibberellins, cytokinins, ethylene, and abscisic acid, regulate plant growth, development, and responses to the environment.
• Tropisms are directional growth responses to environmental stimuli like light (phototropism) and gravity (gravitropism).
• Nastic movements are non-directional responses to stimuli like temperature or touch.

Plant Structure and Anatomy

• Plant anatomy focuses on the internal structure of plants at the cellular and tissue levels.
• Vascular tissues, xylem and phloem, are responsible for the transport of water, minerals, and sugars throughout the plant.
• Xylem transports water and minerals from the roots to the rest of the plant.
• Phloem transports sugars produced during photosynthesis from the leaves to other parts of the plant.
• Roots anchor the plant, absorb water and nutrients, and can sometimes store food reserves.
• Stems provide support for the plant and contain vascular tissues for transport.
• Leaves are the primary sites of photosynthesis in most plants.

Plant Genetics

• Plant genetics is the study of heredity and variation in plants.
• Plant breeding involves the selection and crossing of plants with desirable traits to create improved varieties.
• Genetic engineering allows for the direct modification of a plant's DNA to introduce new traits or enhance existing ones.
• Chromosomes are DNA-containing structures within plant cells that carry genetic information.
• Genes are segments of DNA that encode specific traits.

Plant Ecology

• Plant ecology examines the interactions between plants and their environment.
• Plant communities are groups of plant species that live together in a particular area.
• Succession is the process of change in plant communities over time.
• Plant adaptations are traits that allow plants to survive and reproduce in specific environments.
• Plants have evolved diverse pollination strategies, including wind pollination, insect pollination, and bird pollination.
• Mycorrhizae are symbiotic associations between plant roots and fungi that enhance nutrient uptake.

Plant Distribution and Classification

• Plant taxonomy is the science of classifying and naming plants.
• Plants are classified into a hierarchical system, including kingdoms, phyla, classes, orders, families, genera, and species.
• Plant biogeography studies the distribution of plants around the world and the factors that influence their distribution.
• Endemic species are plants that are found only in a specific geographic area.
• Invasive species are plants that are introduced to a new area and spread aggressively, often outcompeting native species.

Economic Importance of Plants

• Plants provide humans with food, fiber, medicine, and other essential resources.
• Agriculture is the cultivation of plants for food and other products.
• Forestry is the management of forests for timber, recreation, and other purposes.
• Many drugs are derived from plants.
• Plant-derived compounds are used in cosmetics, dyes, and other industries.

Molecular Biology

• Molecular biology is the study of biological processes at the molecular level.
• It focuses on the structure, function, and interactions of macromolecules such as DNA, RNA, and proteins.

DNA Structure and Function

• DNA (deoxyribonucleic acid) is the molecule that carries genetic information in most organisms.
• DNA's structure is a double helix, composed of two strands of nucleotides.
• Each nucleotide consists of a deoxyribose sugar, a phosphate group, and a nitrogenous base.
• The four nitrogenous bases in DNA are adenine (A), guanine (G), cytosine (C), and thymine (T).
• A pairs with T, and G pairs with C.
• DNA replication is the process of copying DNA, ensuring that each new cell receives an identical copy of the genetic material.
• During DNA replication, the double helix unwinds, and each strand serves as a template for the synthesis of a new complementary strand.

RNA Structure and Function

• RNA (ribonucleic acid) is similar to DNA but has a different sugar (ribose) and uses uracil (U) instead of thymine (T).
• RNA is typically single-stranded.
• RNA plays several roles in gene expression, including mRNA (messenger RNA), tRNA (transfer RNA), and rRNA (ribosomal RNA).
• mRNA carries genetic information from DNA to ribosomes for protein synthesis.
• tRNA brings amino acids to the ribosome during protein synthesis.
• rRNA is a component of ribosomes, the cellular structures where protein synthesis occurs.
• Transcription is the process of synthesizing RNA from a DNA template.

Protein Structure and Function

• Proteins are the workhorses of the cell, performing a wide variety of functions.
• Proteins are made up of amino acids linked together by peptide bonds.
• The sequence of amino acids determines the structure and function of a protein.
• Protein folding is the process by which a protein adopts its three-dimensional structure.
• Enzymes are proteins that catalyze biochemical reactions.
• Antibodies are proteins that recognize and bind to foreign substances, such as bacteria and viruses.
• Structural proteins provide support and shape to cells and tissues.

Gene Expression

• Gene expression is the process by which the information encoded in a gene is used to synthesize a functional gene product (protein or RNA).
• Gene expression is regulated at multiple levels, including transcription, translation, and post-translational modification.
• Transcription factors are proteins that bind to DNA and regulate the transcription of genes.
• Translation is the process of synthesizing a protein from an mRNA template.
• Ribosomes are the sites of translation.
• Post-translational modifications, such as phosphorylation and glycosylation, can affect the activity, localization, and interactions of proteins.
• Mutations are changes in the DNA sequence that can alter gene expression and protein function.

Molecular Techniques

• Polymerase chain reaction (PCR) is a technique for amplifying specific DNA sequences.
• Gel electrophoresis is a technique for separating DNA, RNA, or proteins based on their size and charge.
• DNA sequencing is a technique for determining the nucleotide sequence of a DNA molecule.
• Cloning is the process of making identical copies of a DNA molecule or an organism.
• Microscopy techniques, such as electron microscopy and fluorescence microscopy, allow for the visualization of cells and molecules.
• Spectrophotometry is a technique for measuring the absorbance and transmittance of light through a solution, used to quantify the concentration of molecules.

Explore plant physiology, covering photosynthesis, respiration, nutrition, and hormone functions. Understand tropisms as directional growth responses to light and gravity. Nastic movements are non-directional responses to stimuli.