matching BIO notes

Sex Chromosomes: Chromosomes that determine sex, typically X and Y in many organisms.

Histone: Proteins that package DNA into nucleosomes, crucial for regulating gene expression.

Sister Chromatids: Duplicated halves of a chromosome connected by a centromere, separated during cell division.

Centromere: The region of a chromosome where sister chromatids are joined, essential for chromosomal movement during division.

Nucleosome: The fundamental unit of DNA packaging in eukaryotes, consisting of DNA wrapped around histone proteins.

The centromere is found at the constricted region of a chromosome where sister chromatids are joined together. It plays a critical role during cell division, facilitating the proper segregation of chromosomes to daughter cells.

• Sex Chromosomes – Chromosomes that determine an organism’s sex, such as X and Y in many species.

• Histone – A protein that helps package DNA into nucleosomes and regulates gene expression.

• Sister Chromatids – Two identical halves of a duplicated chromosome, joined at the centromere and separated during cell division.

• Centromere – The constricted region of a chromosome where sister chromatids are connected. It ensures proper chromosome movement during cell division. The centromere’s position varies:

• Nucleosome – The basic unit of DNA packaging in eukaryotic cells, made of DNA wrapped around histone proteins.

The centromere is located at the chromosome’s constricted region, where it holds sister chromatids together until they separate during cell division. Its position affects chromosome shape and classification.

Here’s the corrected version for the molecules involved in the electron transfer:

• Molecule 1 – Oxidized (loses electrons)

• Molecule 3 – Reduced (gains electrons)

• Molecule 2 – Reduced first, then oxidized (acts as an intermediate, temporarily holding the electrons before passing them along)

This correctly describes the oxidation-reduction process.

Here’s the corrected and properly matched version of your notes:

• Sugar-Phosphate Backbone – The outer part of the DNA molecule composed of phosphate and sugar molecules, providing structural support.

• Anti-Parallel – The arrangement of the double helix in which the two strands run in opposite directions (one 5’ to 3’, the other 3’ to 5’).

• Complementary – Describes the specific base-pairing rules where adenine (A) pairs with thymine (T) and cytosine (C) pairs with guanine (G) through hydrogen bonding.

• Base Pair – Each step of the DNA ladder, composed of a purine base (A or G) paired with a pyrimidine base (T or C) through hydrogen bonds.

• Double Helix – The twisted, ladder-like shape of DNA, where two strands are linked by base pairs and coiled around an axis.

Here’s the correctly matched and refined version of your notes:

• Diploid – Having two sets of chromosomes (2n), one from each parent.

• Haploid – Having one set of chromosomes (1n), typically found in gametes (sperm and egg cells).

• Chromosome – A compact form of DNA packaged with proteins, essential for genetic organization and inheritance.

• Chromatin – The less condensed form of DNA and proteins found in the nucleus, which condenses into chromosomes during cell division.

• Nucleotide – The monomer of nucleic acids, consisting of a nitrogenous base, a sugar, and a phosphate group.

• Nucleic Acid – An organic macromolecule composed of nucleotides, including DNA and RNA, which store and transmit genetic information.

• Gene – A functional unit of DNA that encodes the amino acid sequence of a protein.