Biomolecules Overview

Biomolecules

• Carbohydrates are short-term energy stores found in plants.
• Monosaccharides are the subunits of sugar.
• A glycosidic bond connects monosaccharides.
• Glucose is found in bread.
• Fructose is found in fruits.
• Galactose is found in dairy products.
• Raffinose is found in beans, cabbages, and whole grains.
• Starch is found in wheat, rice, and potatoes.

Lipids

• Fatty acids are subunits of lipids.
• An ester bond connects fatty acids.
• Lipids are amphiphilic, meaning they have both a polar and nonpolar part.
• The polar head of a lipid is hydrophilic (attracted to water).
• The nonpolar tails of a lipid are hydrophobic (repelled by water).
• Non-saponifiable lipids cannot be broken down by hydrolysis.
• Saponifiable lipids can undergo hydrolysis.
• Nonpolar lipids (triglycerides) are used for energy storage.
• Polar lipids are used in cell membranes.
• Simple lipids are esters of fatty acids and alcohols.
• Fats are simple lipids.
• Waxes are simple lipids.
• Complex lipids include phospholipids, glycolipids, and sterols.
• Phospholipids contain nitrogen-containing bases.
• Glycolipids contain fatty acids, sphingosine, and carbohydrates.
• Sterols have a planar steroid ring (e.g., cholesterol).
• Other complex lipids include amino lipids.
• Fatty acids are carboxylic acids.
• Saturated fatty acids lack carbon-carbon double bonds (butter has higher melting points).
• Unsaturated fatty acids have more than one carbon-carbon double bond (margarine is a trans fat).

Nucleic Acids

• Nucleotides are the subunits of nucleic acids.
• Phosphodiester and hydrogen bonds are types of bonding in nucleic acids.
• Nucleic acids transfer genetic information.
• Nucleic acids synthesize proteins.

Proteins

• Amino acids are the subunits of proteins.
• The peptide bond connects amino acids.
• Proteins have structural and functional roles in organisms.

Photosynthesis

• The law of thermodynamics describes how energy behaves.
• Zeroth law: two systems in equilibrium with a third system are in thermal equilibrium.
• First law: energy cannot be created or destroyed.
• Second law: entropy of an isolated system always increases.
• Third law: entropy approaches zero as temperature approaches zero.
• ATP (adenosine triphosphate) is an energy currency.
• ATP supplies energy for cellular functions.
• Photosynthesis converts light energy to chemical energy using inputs like CO2 and H2O.
• Chlorophyll a and chlorophyll b absorb red and blue light; green light is reflected.
• Light reactions occur in the thylakoid.
• Photophosphorylation is ATP synthesis powered by light through chemiosmosis.
• Electrons flow through the Z-scheme, converting light to chemical energy (as reduced NADPH and ATP).
• Chloroplasts are the site of photosynthesis.
• Chlorophyll a is the main photosynthetic pigment.
• Chlorophyll b is an accessory pigment.
• Dark reactions, or Calvin Cycle, occur in the stroma.

Cellular Respiration

• Cellular respiration converts chemical energy (food) into ATP.
• Cellular respiration involves oxygen consumption and CO2 release.
• Coenzymes in respiration include NAD+ (becomes NADH after picking up electrons and H+) and FAD+ (becomes FADH2 after reduction).
• Glycolysis occurs in the cytoplasm.
• Glycolysis is anaerobic (no oxygen needed).
• Glycolysis produces 2 ATP, 2 NADH, and 2 pyruvates.
• Krebs Cycle (Citric Acid Cycle) occurs in the mitochondrial matrix.

Reproduction

• Asexual reproduction involves one parent, producing genetically identical offspring (clones).
• Examples include fission, fragmentation and regeneration, budding, and sporulation.
• Sexual reproduction involves two parents, resulting in genetically diverse offspring.
• Types of gamete union include isogamy (similar gametes) and heterogamy/oogamy (dissimilar gametes).
• Hermaphrodites are organisms with both male and female reproductive organs.
• Parthenogenesis is development from an unfertilized egg.

Development

• Gastrulation involves the formation of germ layers (ectoderm, mesoderm, endoderm).
• Totipotent cells have the potential to differentiate into any cell type.
• Organogenesis is the development of organ systems.
• Human reproductive systems include male and female systems.
• Male systems include testes, epididymis, vas deferens, scrotum, urethra, seminal vesicle, prostate gland, and Cowper's glands.
• Female systems include ovaries, fallopian tubes, uterus, vagina.
• Menstrual cycle includes ovarian cycle (follicular, ovulation, luteal phases) and uterine cycle (menstrual, proliferative, secretory phases).
• Fertilization occurs in the fallopian tubes.
• Cleavage is a series of mitotic divisions that form a blastula.
• Implantation is when the blastocyst attaches to the uterine wall.
• Gestation refers to the carrying of the embryo or fetus.
• Embryo develops into a fetus.
• Growth is an increase in size.
• Monozygotic twins result from the splitting of a single zygote (identical twins).
• Dizygotic twins result from the fertilization of two separate eggs (fraternal twins).

Parts of a Flower

• Sepals are the outermost whorl of a flower.
• Petals form the corolla.
• Stamen is the male part of the flower, including anther and filament.
• Pistil/carpel is the female part of the flower, including stigma, style, and ovary.

Types of Flowers

• Complete flowers contain sepals, petals, stamens, and carpels.
• Incomplete flowers lack one or more of the whorls.
• Monoecious plants have separate male and female flowers on one plant.
• Dioecious plants have male and female flowers on different plants.
• Perfect/bisexual flowers contain both stamens and carpels.
• Imperfect/unisexual flowers have either stamens or carpels.

Plant Life Cycles

• Gametophyte produces gametes.
• Sporophyte produces spores.
• In haploid life cycles the dominant stage is the haploid gametophyte.
• In diplontic life cycles the dominant stage is the diploid sporophyte.
• In haplodiplontic life cycles both haploid and diploid stages are prominent.

Contraception

• Methods include hormonal, barrier, and surgical.

This quiz covers the basic concepts of biomolecules, focusing on carbohydrates and lipids. You'll learn about the structures, functions, and examples of these essential organic compounds found in living organisms. Test your knowledge on sugar subunits, fatty acids, and their roles in energy storage and cell structure.