Biology 1010 Midterm Study Guide (Modules 2-6)

Comprehensive practice flashcards covering vocabulary, key processes, and definitions from Modules 2 through 6 for the Biology 1010 midterm exam.

Ionic bond

A chemical bond in which electrons are given and taken, resulting in the formation of ions.

Covalent bond

A chemical bond characterized by shared electrons between atoms.

Hydrogen bond

A bond that forms between partial charges on hydrogen-containing molecules, such as between the negative oxygen end of one water molecule and the positive hydrogen end of another water molecule.

Water polarity

The property of a water molecule resulting from two polar covalent bonds between hydrogens and oxygen, causing an uneven distribution of charge.

Carbon

The elemental backbone of all organic molecules.

Monosaccharide

The monomer building block of carbohydrates, such as glucose.

Lipids

A class of macromolecules composed of C, H, and O whose defining characteristic is being hydrophobic (non-polar).

Components of a fat

Glycerol and fatty acid(s).

Polypeptide

A chain of amino acids that forms a protein, whose specific shape determines its biological function.

Nucleic acids

Macromolecules composed of the elements C, H, O, N, and P, with polymer examples being DNA and RNA.

Cell membrane

A biological barrier whose key structural components are a phospholipid bilayer and embedded proteins.

Phospholipid

A key membrane component consisting of a polar "head" and two non-polar "tails".

Diffusion

A passive transport process that moves small molecules, such as oxygen and carbon dioxide, down their concentration gradient.

Facilitated diffusion

A passive transport process that moves specific molecules, such as glucose, across a membrane without energy expenditure.

Osmosis

A passive transport process specifically defined as the net movement of water across a membrane.

Active transport

An energy-requiring cellular transport process that moves ions, such as $Na^+$ and $K^+$ ions, against their concentration gradient.

Endocytosis

An active transport process that engulfs bulk materials, such as proteins and bacterial cells, into the interior of the cell.

Exocytosis

An active transport process that packages and expels materials, such as proteins and waste, out of the cell.

Adenosine Triphosphate (ATP)

The primary energy currency utilized by cells to drive biological work.

Enzyme

A molecular catalyst that increases reaction rate by lowering the activation energy barrier.

Activation energy

The initial energy threshold required to trigger a chemical reaction, which enzymes lower to accelerate reaction rates.

Cellular respiration

A metabolic process that breaks down reactants such as glucose in the presence of oxygen to produce ATP, carbon dioxide, and water.

Glycolysis

The initial stage of cellular respiration that takes place in the cell cytoplasm and generates ATP output.

Kreb's cycle

A stage of cellular respiration occurring in the cell that produces ATP and releases carbon dioxide.

Electron transport chain

A stage of cellular respiration that requires the presence of oxygen and produces ATP.

Anaerobic cell respiration

A cellular respiration pathway operating in the absence of oxygen, differing from aerobic respiration in the products formed and yielding a lower amount of ATP.

Photosynthesis

The biological process by which plants use light energy, water, and carbon dioxide to produce sugars and oxygen.

Stoma

A key plant structure (pore) critical to photosynthesis that regulates gas exchange.

Chloroplast

The specialized plant cell organelle where both light-dependent reactions and the Calvin cycle take place.

Light-Dependent Reactions

Photosynthetic reactions that occur in the chloroplast, use light and water, produce oxygen, and generate ATP and NADPH for the Calvin cycle.

Calvin Cycle

Photosynthetic reactions that occur in the chloroplast, consume carbon dioxide along with ATP and NADPH from the light reactions, and produce sugar.

Sister chromatids

Two identical copies of a duplicated chromosome produced during replication that remain joined together.

Nucleotide

The fundamental building block of DNA, composed of a deoxyribose sugar, a phosphate group, and a nitrogen base (adenine, thymine, cytosine, or guanine).

Interphase

The non-dividing phase of the cell life cycle consisting of G1, S, and G2 subphases.

S phase

The specific time within interphase during which all of the DNA in a cell is copied via DNA replication prior to cell division.

DNA polymerase

The enzyme that catalyzes the addition of new nucleotides to single-stranded template DNA according to base-pairing rules during DNA replication.

Prophase

The first phase of mitosis during which chromosomes condense.

Metaphase

The mitotic phase in which duplicated chromosomes line up along the middle of the cell.

Anaphase

The stage of mitosis during which sister chromatids separate and move toward opposite poles.

Telophase

The final stage of mitosis in which nuclei form around the separated chromosomes and the cell returns to a non-dividing state.

Cytokinesis

The division of the cytoplasm that overlaps mitosis, culminating in two distinct daughter cells.

Proto-oncogenes

Normal genes that carry instructions to regulate the cell cycle, which can lead to cancer when mutated.

Tumor suppressor genes

Genes carrying instructions to regulate and restrain cell division within the cell cycle, which can lead to cancer when mutated.

Asexual reproduction

A mode of reproduction that results in genetically identical descendants.

Sexual reproduction

A mode of reproduction that combines genetic material from two parents to generate genetic variation in offspring.

Diploid cell

A body cell (non-sex cell) containing pairs of homologous chromosomes; designated as $2n$, with 46 being the diploid chromosome number in humans.

Haploid cell

A gamete (sex cell) containing unpaired chromosomes; designated as $n$, with 23 being the haploid chromosome number in humans.

Autosomes

Body chromosomes numbered 1 through 22 that are present in every cell of the human body.

Sex chromosomes

The 23rd chromosome pair (XX in chromosomal females and XY in chromosomal males) responsible for primary sex determination.

Gamete

A haploid sperm or egg cell, also known as a sex cell.

Zygote

A diploid fertilized egg cell that undergoes repeated rounds of mitosis during embryonic development.

Meiosis I

A unique nuclear division stage featuring crossing over in prophase I and the separation of homologous chromosome pairs, resulting in two haploid daughter cells.

Meiosis II

A nuclear division process similar to mitosis that separates sister chromatids, resulting in four haploid cells (potential gametes).

Crossing over

A process occurring during prophase I of meiosis where homologous chromosome pairs exchange segments of DNA, serving as a key source of genetic variation.

Nondisjunction

The failure of homologous chromosome pairs or sister chromatids to separate properly during meiosis, which can lead to aneuploidy.