Biology Lecture Flashcards: Genetics and Metabolism

Flashcards based on lecture notes covering Mendelian genetics, chromosomal inheritance, photosynthesis, cellular respiration, metabolism, and cell communication.

Mendel

The father of genetics who discovered how traits are inherited.

Chromosome theory of inheritance

The theory stating that genes are located on chromosomes.

Locus (loci)

The specific location of a gene on a chromosome.

Alleles

Different versions of a gene.

Wild-type phenotype

The normal phenotype commonly found in nature.

Mutant phenotype

An alternative trait or phenotype resulting from a mutation.

Sex-linked genes

Genes located on the X or Y chromosomes.

X-linked recessive disorders in males

Disorders that are more common in males because they only require one copy of the allele ($XY$) to be expressed.

X-linked recessive inheritance in females

To express a trait, a female needs two copies of the allele (homozygous).

Examples of X-linked disorders

Color blindness, Hemophilia, and Duchenne muscular dystrophy.

X-inactivation

The process in females where one X chromosome is turned off.

Barr body

The inactive X chromosome.

Linked genes

Genes that are located on the same chromosome and tend to be inherited together.

Recombinants

Offspring that possess new combinations of traits different from their parents.

Crossing over

The event during meiosis that causes genetic recombination.

50% recombination frequency

Indicates that the genes are unlinked and located on different chromosomes.

Nondisjunction

An error in meiosis where chromosomes fail to separate properly.

Aneuploidy

A condition characterized by an abnormal number of chromosomes.

Monosomy vs. Trisomy

Monosomy is having 1 copy of a chromosome; Trisomy is having 3 copies.

Down syndrome

A specific example of a trisomy disorder.

Photosynthesis

The process that converts light energy into chemical energy.

Chloroplasts

The organelles where photosynthesis occurs.

Thylakoids

Membrane sacs where the light reactions of photosynthesis happen.

Stroma

The fluid within the chloroplast where the Calvin cycle occurs.

Light reactions products

$ATP$, $NADPH$, and $O_2$.

Water ($H_2O$) splitting

The molecule split during light reactions to provide electrons.

G3P

The sugar precursor produced by the Calvin cycle.

Calvin cycle requirements

This process uses $ATP$ and $NADPH$ to produce sugar.

Carbon fixation

The conversion of $CO_2$ into an organic molecule.

Cellular respiration goal

To produce $ATP$ from glucose.

Cellular respiration equation

$$\text{Glucose} + O_2 \rightarrow CO_2 + H_2O + ATP$$

Three stages of respiration

Glycolysis, Citric Acid Cycle, and Oxidative Phosphorylation.

Glycolysis

The stage of respiration occurring in the cytoplasm that yields a net of $2\,ATP$.

Oxygen ($O_2$) in respiration

The final electron acceptor in the electron transport chain.

End products of the Electron Transport Chain

Water ($H_2O$) and a large amount of $ATP$.

Fermentation

An anaerobic process that occurs when no oxygen is present to regenerate $NAD^+$.

Types of fermentation

Alcohol fermentation and Lactic acid fermentation.

Catabolic vs. Anabolic

Catabolic reactions break down molecules and release energy; Anabolic reactions build molecules and require energy.

ATP

The energy currency of the cell.

Exergonic reaction

A reaction that releases energy.

Endergonic reaction

A reaction that requires an input of energy.

Enzymes

Proteins that speed up reactions without changing the $\Delta G$.

Activation energy

The energy required to start a chemical reaction.

Active site

The location on an enzyme where the substrate binds.

Stages of cell signaling

Reception, Transduction, and Response.

Ligand

A signaling molecule that binds to a specific receptor.

Second messengers

Molecules like $cAMP$ and $Ca^{2+}$ that relay signals inside the cell.

Apoptosis

Programmed cell death.

Where does the Calvin cycle occur?

Stroma of chloroplast

What is the purpose of the Calvin cycle?

Produce G3P (sugar)

What are the inputs of the Calvin cycle?

CO2 ATP NADPH

What is the output of the Calvin cycle?

G3P

What are the 3 phases of the Calvin cycle?

Carbon fixation reduction regeneration

Where does the Krebs (citric acid) cycle occur?

Mitochondrial matrix

What is the purpose of the Krebs cycle?

Produce electron carriers for ATP production

What is the input of the Krebs cycle?

Acetyl-CoA

What are the outputs of the Krebs cycle?

ATP NADH FADH2 CO2

What do NADH and FADH2 do?

Carry electrons to the electron transport chain

Where does the electron transport chain occur?

Inner mitochondrial membrane

What is the purpose of the electron transport chain?

Produce most ATP

What powers ATP synthase?

Proton gradient

What is the final electron acceptor in the ETC?

Oxygen

What is produced when oxygen accepts electrons?

Water

What is chemiosmosis?

Use of a proton gradient to make ATP

What is the overall flow of cellular respiration?

Glycolysis Krebs cycle electron transport chain

What uses NADPH?

Calvin cycle

What produces ATP in photosynthesis?

Light reactions

What is the difference between cyclic and linear electron flow?

Cyclic makes ATP only linear makes ATP NADPH and oxygen