Table of Contents
Fertilization in Humans
Fertilization in humans occurs when the head of the sperm penetrates the egg cell, or ovum. The sperm carries the male’s genetic information and the egg carries the female’s genetic information. The genetic material from the two cells combines to create a new, genetically unique individual.
Steps Involved in Fertilization in Humans
The process of fertilization in humans takes place in the fallopian tubes. When a woman is sexually aroused, her body releases a hormone called oxytocin. This hormone causes the muscles in the fallopian tubes to contract, which helps the sperm travel to the egg. The sperm and the egg meet in the fallopian tubes, and the sperm fertilizes the egg. The fertilized egg then travels to the uterus, where it implants in the lining and begins to grow.
Cortical Reaction
Time
Cortical Reaction Time (CRT) is the time it takes for a stimulus to travel from the retina to the cortex. The time it takes for a response to be generated in the cortex is also included in CRT. CRT is important for activities that require the quick processing of visual information, such as driving a car or playing a sport.
Sperm Entry
into the Uterus
The uterus is the female reproductive organ in which a baby grows during pregnancy. The cervix is the opening of the uterus that is located at the top of the vagina. The sperm travel through the cervix and into the uterus where the egg is located.
Karyogamy
Karyogamy is the fusion of two haploid nuclei to form a diploid nucleus. This process is important for sexual reproduction, as it allows for the combination of genetic information from two parents to create a new individual.
Activation of Eggs
When an egg is fertilized by a sperm, the egg’s cell membrane undergoes a change that allows the entry of the sperm nucleus. The egg’s cytoplasm then begins to divide by mitosis, and the embryo begins to develop.
Implantation
The process of implantation begins after the sperm has fertilized the egg. The fertilized egg, now called a zygote, begins to divide and grow. It will divide several times as it travels down the fallopian tube to the uterus. The zygote will become a ball of cells called a morula. The morula will then become a hollow ball of cells called a blastocyst.
The blastocyst will implant into the wall of the uterus. The implantation process takes about six days. The blastocyst will attach to the wall of the uterus and send out tiny projections that will dig into the uterine wall. The blastocyst will also release chemicals that will help to attach it to the uterine wall.
The embryo will then begin to grow and develop. The development of the embryo will be affected by the environment of the uterus. The uterus will provide the embryo with the nutrients it needs to grow and the hormones it needs to develop.
Sex Determination
One of the most important aspects of sex determination is chromosomal sex. The sex chromosomes are the chromosomes that determine the sex of an individual. There are two types of sex chromosomes, X and Y. Females have two X chromosomes, while males have one X and one Y chromosome.
The sex chromosomes are important in sex determination because they contain the genes that determine sex. The genes on the sex chromosomes are called sex-determining genes. The sex-determining genes are responsible for the development of the reproductive organs.
The Y chromosome contains the gene that causes the development of the testes. The testes are the organs that produce the male sex hormones, testosterone and sperm. The testosterone is responsible for the development of the male reproductive organs, while the sperm carries the male DNA.
The X chromosome contains the gene that causes the development of the ovaries. The ovaries are the organs that produce the female sex hormones, estrogen and eggs. The estrogen is responsible for the development of the female reproductive organs, while the eggs carry the female DNA.
The sex chromosomes are also responsible for the development of the brain. The testosterone produced by the testes causes the development of the male brain, while the estrogen produced by the ovaries causes the development of the female brain.
The sex chromosomes are also responsible for the development of the behavior of males and females. The testosterone produced by the testes causes the development of the aggressive and dominant behavior
