vasta Flashcards
What is sexual reproduction?
Producing of new organisms/offsprings by the combination of genetic information of two organisms
How many chromosomes does the human body have?
46 chromosomes (23 pairs)
What are homologous chromosomes?
Two chromosomes that make up a pair derived from both parents
What are gametes?
Sex cells that have half the number of chromosomes (23)
What does haploid mean?
n number of cells
What is fertilization?
The haploid gametes of two parents combine, making 2n of chromosomes, called a diploid or zygote
What is meiosis?
Formation of gametes, referred to as reduction division
What occurs during interphase in meiosis?
DNA replication
What happens during prophase in meiosis?
Crossing over occurs, exchanging segments between homologous chromosomes
What occurs during metaphase in meiosis?
Homologous chromosomes line up in the equator of the cell
What happens during anaphase in meiosis?
Homologous chromosomes separate
What occurs during telophase in meiosis?
Homologous chromosomes reach opposite poles of the cell
What is cytokinesis in meiosis?
Formation of 2 haploid daughter cells
What is the purpose of mitosis?
Tissue repair / replacement, organismal growth, asexual reproduction in plants, development of embryos
What is the first step in the mechanisms of sexual reproduction?
An egg (ovum) is released from the ovary during ovulation
What happens to the egg after ovulation?
The egg travels through the fallopian tube for potential fertilization
How do sperm reach the egg?
Sperms swim through the cervix and into the uterus, reaching the fallopian tube
What occurs if a sperm successfully penetrates the egg?
Fertilization occurs, forming a zygote
What marks the beginning of a new individual?
The zygote containing a combination of genetic material from both the egg and sperm
What is the early stage of pregnancy?
Zygote to blastocyst
What happens during implantation?
The blastocyst implants itself into the lining of the uterus
What occurs during embryo formation?
Cells differentiate into embryonic tissues, and the embryo begins to form
What are the advantages of sexual reproduction?
Offspring variation, survival, adaptation, shuffling of genes, elimination of harmful genes
What does the cell cycle describe?
The sequence of cell growth and division in a eukaryotic somatic cell
