Chapter 3 Flashcards
What is the first cell that we become?
Zygote
Heredity
Genetic transmission of characteristics from parents to children
How is the first cell created?
Sperm pushes through the membrane of the ovum; they fuse together to form a zygote
What are gametes?
The male and female reproductive/sex cells that form a new cell at conception/fertilization
Fertilization
Process where gametes join to form zygote
Zygote
New cell created via fertilization
What do gametes contain?
Genetic information that is transferred via chromosomes during fertilization
genes
basic biological units of genetic information and inheritance
what is the russian doll analogy of genetics
cell –> inside the nucleus is 23 pairs of chromosomes (except gametes) –> in these chromosomes are genes —> genes are segments of DNA
what do genes influence
physical characteristics and have the instructions for making proteins
What is DNA
the substance that genes are composed of that determines the function and nature of every cell in the body
what are genes arranged in
specific order and location along 46 chromosomes
chromosomes
rod shaped portions of DNA that have 23 matching pairs
TF: all pairs of chromosomes are the same
false; 23rd pair differs from its member of the pair and it determines the sex
how many chromosomes do the gametes have and how do parents contribute to the total number of chromosomes
23 chromosomes in nucleus of gametes; mother and father each contribute 23 chromosomes each to make the 46 chromosomes the zygote
what is mitosis
process of cell replication, ensuring every cell has same chromosomes as zygote
meiosis
process of cell division that creates gametes
Monozygotic twins aka
identical
monozygotic twins are created when
cluster of cells in the ovum split off after fertilization; creating 2 identical zygotes that were from 1 original zygote
monozygotic twin
twins that are genetically identical
what is responsible for differences between monozygotic twins
environmental factors
how are dizygotic twins created?
when two separate ova are fertilized by two separate sperm at roughly the same time
dizygotic twins are no more similar than
siblings born at different times