Unit 2 - The Molecular Composition of Plant Cells Flashcards
What are four major types of organic molecules?
carbohydrates (consisting of sugars and chains of sugars),
lipids (most of which contain fatty acids), proteins (composed
of amino acids), and nucleic acids (DNA and RNA)
What are Carbohydrates?
Primary energy-storage molecules in most living
organisms. The simplest carbohydrates are small molecules known as
sugars
What are three principal kinds of carbohydrates?
Monosaccharides (“single, or simple, sugars”), such as
ribose, glucose, and fructose, consist of only one sugar molecule.
Disaccharides (“two sugars”) contain two sugar subunits
linked covalently. Familiar examples are sucrose (table sugar),
maltose (malt sugar), and lactose (milk sugar). Cellulose and
starch are polysaccharides (“many sugars”), which contain
many sugar subunits linked together.
What is hydrolysis?
hydro, meaning “water,” and lysis, “breaking apart.” Hydrolysis
reactions are energy-yielding processes that are important in energy
transfers in cells.
What are Lipids?
Lipids are fats and fatlike substances. Typically, lipids serve as energy-storage molecules—usually in
the form of fats or oils.
What is biological membrane?
Membrane, in biology,the thin layer that forms the outer boundary of a living cellor of an internal cell compartment.
What are epidermal cells?
Epidermal cells are the outermost layer of cells in a plant, covering the stems, leaves, roots, flowers, fruits, and seeds.They protect the plant from water loss, infection, and mechanical injury.
What are proteins?
they are all polymers of nitrogen-containing molecules
known as amino acids, arranged in a linear sequence.
What are enzymes?
Enzymes are large, complex globular proteins that act as catalysts.
By definition, catalysts are substances that accelerate
the rate of a chemical reaction by lowering the energy of activation,
but remain unchanged in the process
What are Nucleid Acids?
Nucleic acids consist of long chains of molecules known as nucleotides. A nucleotide, however,
is a more complex molecule than an amino acid.
What are two types of Nucleic Acids?
Two types of nucleic acids are found in living organisms.
In ribonucleic acid (RNA), the sugar subunit in the nucleotides
is ribose. In deoxyribonucleic acid (DNA), it is deoxyribose.
What is ATP?
the carriers of the energy needed to power the
numerous chemical reactions occurring within cells.
The principal energy carrier for most processes in living
organisms is the molecule adenosine triphosphate, or ATP
What are Primary metabolites?
Primary metabolites, by definition, are molecules that are found in
all plant cells and are necessary for the life of the plant.
Examples
of primary metabolites are simple sugars, amino acids, proteins,
and nucleic acids.
What are secondary metabolites?
Secondary metabolites, by contrast, are
restricted in their distribution, both within the plant and among
the different species of plants. Once considered waste products,
secondary metabolites are now known to be important for the
survival and propagation of the plants that produce them. Many
serve as chemical signals that enable the plant to respond to environmental
cues. Others function in the plant’s defense against
herbivores, pathogens (disease-causing organisms), or competitors.
Some provide protection from radiation from the sun, while
still others aid in pollen and seed dispersal.
What are pathogens?
A pathogen isan organism or agent that can cause disease in a host.Pathogens include viruses, bacteria, and other microorganisms
What does metabolite means?
A metabolite is a substance that is produced when the body breaks down food, drugs, chemicals, or its own tissue. The process of breaking down substances is called metabolism.
Examples of metabolites amino acids, vitamins, and hormones
