Biology: Photosynthesis, Cellular Respiration, and Genetic Inheritance

What is the balanced chemical equation for photosynthesis?

6CO2 + 6H2O + light energy -> C6H12O6 + 6O2

What is the primary energy source for photosynthesis?

Solar radiation (sunlight)

What is the balanced chemical equation for aerobic cellular respiration?

C6H12O6 + 6O2 -> 6CO2 + 6H2O + ATP

What is the biological purpose of aerobic cellular respiration?

To break down glucose to generate usable ATP energy for cellular work.

Which organisms can perform photosynthesis?

Plants, multicellular/unicellular algae (protists), and cyanobacteria (photosynthetic eubacteria).

What stage of cellular respiration generates the majority of ATP?

The Electron Transport Chain (ETC) / Oxidative Phosphorylation

Where does the Electron Transport Chain take place?

Across the inner mitochondrial membrane (cristae).

What happens when ATP releases energy to become ADP?

A water molecule is used to split the bond (hydrolysis) between the second and third phosphate groups, releasing a free phosphate and energy.

What is the fundamental difference in cell cycle regulation between cancer cells and normal cells?

Cancer cells bypass standard cell cycle checkpoints due to accumulated genetic mutations, leading to uncontrolled cell division.

What unique capability do stem cells have?

They are unspecialized cells capable of indefinite self-renewal and can differentiate into specific, functional cell types.

What is the outcome of a single diploid parent cell undergoing standard Mitosis?

Two genetically identical diploid (2n) daughter somatic cells.

What is the outcome of a single diploid parent cell undergoing standard Meiosis?

Four genetically diverse haploid (n) daughter gametes.

What is the chromosome count for a cell with 24 chromosomes undergoing Mitosis?

2 cells with 24 chromosomes each.

What is the chromosome count for a cell with 24 chromosomes undergoing Meiosis?

4 cells with 12 chromosomes each.

What is the complete monomer structure of a DNA molecule?

A single nucleotide, consisting of a deoxyribose sugar, a phosphate group, and one nitrogenous base (A, T, C, or G).

How do you apply Chargaff's Rule if Adenine is 32%?

Thymine is also 32%, and the remaining 36% is split equally between Cytosine and Guanine (18% each).

How does semi-conservative DNA replication preserve genetic sequences?

Parent strands unzip, and each original strand acts as a template to construct a new complementary daughter strand.

What is the contrast between Transcription and Translation?

Transcription occurs in the nucleus to rewrite DNA into mRNA; Translation occurs at the ribosome to decode mRNA into a functional protein.

How does a ribosome read an mRNA codon chart?

It reads the mRNA strand in sequential groups of three nitrogenous bases (codons) from 5' to 3'.

What is the difference between genotype and phenotype?

Genotype is the combination of inherited alleles, while phenotype is the physical trait expressed.

What is the purpose of constructing a Punnett square?

To calculate and predict the statistical probabilities of genotypic and phenotypic outcomes among offspring.

What is the phenotypic difference between Incomplete Dominance and Codominance?

Incomplete dominance results in a blended phenotype; codominance results in both traits being fully expressed.

What is the genetic difference between Multiple Alleles and Polygenic Inheritance?

Multiple alleles involve more than two alternative alleles for a single gene; polygenic inheritance involves multiple genes controlling one trait.

What are the offspring probabilities from a heterozygous Type A parent (IAi) and a Type AB parent (IAIB)?

50% Type A (IAIA, IAi), 25% Type AB (IAIB), and 25% Type B (IBi).

How can you determine if a pedigree trait is dominant or recessive?

If two unaffected parents have an affected child, the trait is recessive; if every affected child has an affected parent, it is dominant.

How is a standard pedigree chart structured?

Generations are listed vertically using Roman numerals, and individual family members are numbered left to right using Arabic numerals.

What is the core definition of natural selection?

The process where organisms with heritable traits better adapted to environmental pressures survive and reproduce at higher rates.

What are the 4 requirements for natural selection to operate?

1. Overproduction of offspring, 2. Inherited genetic variation, 3. Competitive struggle for survival, 4. Differential reproductive success.

What is a historical example of natural selection?

The shift of peppered moth populations from light to dark coloring during the Industrial Revolution.

What is biological evolution?

The change in a population's genetic composition over time.

What are the major categories of evidence supporting biological evolution?

Fossil record, anatomical comparisons, embryology, and molecular/DNA sequencing.

What is the approximate age of planet Earth?

~4.6 billion years old.

What were the chemical characteristics of Earth's primitive atmosphere?

Highly volatile, containing methane, ammonia, carbon dioxide, and water vapor, but lacked free oxygen (O2).

How do Stabilizing, Directional, and Disruptive selection modify a population phenotype graph?

Stabilizing narrows the graph; Directional shifts it toward one extreme; Disruptive splits it into two peaks.

What is the standard taxonomic ranking system from broadest to most specific?

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species.

What are the core differences between prokaryotes and eukaryotes?

Prokaryotes lack a membrane-bound nucleus and organelles; Eukaryotes have a true nucleus and complex organelles.

Which taxonomic Kingdoms contain autotrophic organisms capable of photosynthesis?

Kingdom Plantae, Kingdom Protista (algae), and Kingdom Eubacteria (cyanobacteria).

What is the cellular structural difference between Eubacteria and Archaebacteria?

Eubacteria contain peptidoglycan in their cell walls; Archaebacteria lack peptidoglycan and have unique membrane lipids.

Why are viruses excluded from biological classification domains?

They are non-cellular, lack independent metabolic processes, and cannot reproduce without a host cell.

How can you determine close evolutionary relationships using a cladogram?

Organisms sharing a more recent common ancestor are more closely related.