Genetics and Cell Biology Test Flashcards
Learn definitions (15 cards)
List the levels of organization from organism to DNA
Organelle, Cell, Tissue, Organs, Organ systems, Organism
Describe the relationship between cells, DNA, and genes
Cells are the basic units of life that contain a nucleus where DNA is stored. DNA is a long sequences of nucleotides that carry genetic instructions for the cell’s functions. Genes are specific sections of DNA that code for proteins, determining an organism’s traits and characteristics.
What are genes, and what is their function?
Genes are segments of DNA that contain instructions for making proteins, which are essential for the structure and function of cells. Their function is to determine an organism’s traits by controlling biological processes like growth, development, and metabolism.
Draw a nucleotide
Phosphate group, Sugar deoxyribose, Base pairings.
Name three different mutagens that can affect the genetic code
Radiation, Chemicals, Viruses
Define what a mutagen is
A mutagen is any physical, chemical, or biological agent that causes changes (mutations) in an organism’s DNA, potentially leading to genetic alterations. These mutations can affect cell function, sometimes leading to diseases like cancer.
Define the term sex chromosome
A sex chromosome is a type of chromosome that determines an organism’s biological sex. In humans, there are two types: X and Y—males have one X and one Y (XY), while females have two X chromosomes (XX).
Define the term autosome
An autosome is any chromosome that is not a sex chromosome. Humans have 22 pairs of autosomes, which contain genes responsible for most of the body’s traits and functions, unrelated to biological sex.
Briefly explain what happens in each stage of mitosis
Prophase - Chromosomes condense, the nuclear membrane breaks down, and spindle fibers begin to form.
Metaphase - Chromosomes align in the center of the cell, attatched to spindle fibres.
Anaphase - Sister chromatids are pulled apart to opposite sides of the cell.
Telophase - Two new nuclei form around the seperated chromosomes, and the cell begins to divide.
Describe the process of fertilization
Fertilization is the process where a male sperm cell and a female egg cell fuse to form a zygote. It begins when a sperm reaches and penetrates the egg, usually in the fallopian tube. The sperm’s nucleus merges with the egg’s nucleus, combining genetic material from both parents to create a unique diploid cell, which then begins to divide and develop into an embryo.
Explain how sexual reproduction results in genetic variation
Sexual reproduction results in genetic variation through meiosis.
Define the relationship between DNA, chromosomes, genes and traits
DNA is the genetic material that contains instructions for building and maintaining an organism. It is organized into chromosomes, which are long strands of DNA found in the nucleus of cells. Genes are specific segments of DNA on chromosomes that carry the instructions for making proteins, which control various biological functions. These proteins influence the organism’s traits, such as eye color or height, by affecting how cells, tissues, and organs function.
Define the terms genotype and phenotype
Genotype refers to the genetic makeup of an organism, specifically the combination of alleles inherited from both parents for a particular trait. Phenotype is the observable physical or behavioral characteristics of an organism, which result from the interaction of its genotype with the environment.
Define dominant traits
Dominant traits are characteristics that are expressed in an organism even if only one copy of the dominant allele is present in the genotype. They mask the effect of a recessive allele when both are present, and the dominant allele determines the trait’s appearance.
Define recessive traits
Recessive traits are characteristics that are only expressed when two copies of the recessive allele are present in the genotype, one inherited from each parent. If a dominant allele is present, it will mask the expression of the recessive trait.
