Unit 2 AOS 1 Sac Flashcards
What are homologous chromosomes, and how do they differ from autosomes and sex chromosomes?
Homologous chromosomes are pairs of chromosomes with the same gene loci; autosomes are non-sex chromosomes, while sex chromosomes determine an organism’s sex.
Question: What is the distinction between genes, alleles, and a genome?
A gene is a segment of DNA that codes for a protein, an allele is a variant form of a gene, and the genome is the complete set of genetic material in an organism.
What is a karyotype, and how is it used?
A karyotype is a visual representation of chromosomes arranged by size and shape, used to identify chromosome abnormalities
: How do chromosomes vary among different organisms?
Chromosomes vary in size, number, and structure across different organisms, contributing to genetic diversity.
: What is the purpose of meiosis, and how does it differ from mitosis?
The purpose of meiosis is to produce unique haploid gametes with half the genetic complement of the parent cell, differing from mitosis, which produces identical diploid cells.
How do meiosis I and meiosis II differ in chromosome division?
Answer: Meiosis I separates homologous chromosomes, while meiosis II separates sister chromatids.
How does crossing over and independent assortment contribute to genetic diversity?
Crossing over and independent assortment during meiosis create new combinations of genes, increasing genetic variation.
What is the difference between complete dominance, codominance, and incomplete dominance?
Complete dominance occurs when one allele masks another, codominance when both alleles are expressed equally, and incomplete dominance when a heterozygous phenotype is intermediate.
What are multiple alleles and sex linkage?
Multiple alleles refer to more than two possible alleles for a gene, and sex linkage refers to genes located on sex chromosomes, often affecting traits like color blindness.
What is pedigree analysis, and what does it reveal?
Pedigree analysis charts inheritance patterns across generations, revealing autosomal and sex-linked inheritance of traits.
What is a monohybrid cross, and how is it used in genetics?
A monohybrid cross predicts the outcome of a cross between two organisms with different alleles for a single gene, often used to determine dominant and recessive traits.
How does DNA code for proteins, and what roles do enzymes and protein channels play?
DNA codes for proteins by specifying amino acid sequences; enzymes catalyze reactions, while protein channels facilitate molecule movement across the plasma membrane.
What is chromatin, and how does it relate to chromosomes?
Chromatin is decondensed DNA within the nucleus, which condenses to form chromosomes during cell division.
What is the basic structure of a nucleotide?
A nucleotide consists of a phosphate group, a deoxyribose sugar, and a nitrogenous base (A, T, C, or G).
What is aneuploidy, and how does it differ from polyploidy?
Aneuploidy is the presence of an abnormal number of chromosomes (e.g., trisomy 21), while polyploidy involves having more than two complete sets of chromosomes.
