Mitosis and Meiosis difference - Biology, EXTRA BIO! 6.2
oviduct
(also, fallopian tube) muscular tube connecting the uterus with the ovary area
Know steps of Mitosis.
.
Describe the phases of the human sexual response.
In phase one (excitement), vasodilation leads to vasocongestion and enlargement of erectile tissues. Vaginal secretions are released to lubricate the vagina during intercourse. In phase two (plateau), stimulation continues, the outer third of the vaginal wall enlarges with blood, and breathing and heart rate increase. In phase three (orgasm), rhythmic, involuntary contractions of muscles occur. In the male, reproductive accessory glands and tubules constrict, depositing semen in the urethra; then, the urethra contracts, expelling the semen through the penis. In women, the uterus and vaginal muscles contract in waves that may last slightly less than a second each. In phase four (resolution), the processes listed in the first three phases reverse themselves and return to their normal state. Men experience a refractory period in which they cannot maintain an erection or ejaculate for a period of time ranging from minutes to hours. Women do not experience a refractory period.
Where does oogenesis occur?
In the ovaries before birth
Where are the gametes located?
In the reproductive organs
Name the four difference between mitosis in Meiosis.
Mitosis - makes genetically identical cells, makes diploid cells, takes place throughout an organism's lifetime, and is involved in asexual reproduction Meiosis - makes unique cells, makes haploid cells, takes place at a certain time in an organism's lifetime, and is involved in sexual reproduction
What are sister chromatids?
One half of a chromosome and they are duplicates of each other
What is an immature egg called?
Oocyte
What are polar bodies? Where are polar bodies made in the male or in the female?
Polar bodies on the smaller cells produced by meiosis in the female
When does crossing over occur?
Prophase one
What is independent assortment?
Random alignment and it is also what makes you look different than every one else
What are gametes?
Sex cells (egg and sperm) that have DNA that will be passed on to offspring
What is anaphase two?
Sister chromatids are separated and move to the opposite sides of the cells.
What are the two major groups of cell types in human body?
Somatic and sex cells
gameotogenesis in males
Sperm becomes streamlined and motile Sperm primarily contributes DNA to an embryo
What is an immature sperm called?
Spermatids
Compare spermatogenesis and oogenesis as to timing of the processes and the number and type of cells finally produced.
Stem cells are laid down in the male during gestation and lie dormant until adolescence. Stem cells in the female increase to one to two million and enter the first meiotic division and are arrested in prophase. At adolescence, spermatogenesis begins and continues until death, producing the maximum number of sperm with each meiotic division. Oogenesis continues again at adolescence in batches of oogonia with each menstrual cycle. These oogonia finish the first meiotic division, producing a primary oocyte with most of the cytoplasm and its contents, and a second cell called a polar body containing 23 chromosomes. The second meiotic division results in a secondary oocyte and a second oocyte. At ovulation, a mature haploid egg is released. If this egg is fertilized, it finishes the second meiotic division, including the chromosomes donated by the sperm in the finished cell. This is a diploid, fertilized egg.
Which chromosome carries the fewest number of genes?
The Y chromosome
Fertilization
The action of fertilizing an egg involving the fusion of male and female gametes to form a zygote
What happens in prophase one?
The nuclear membrane of the diploid cell breaks down and duplicated homologous chromosomes begin to pair up. Spindle fibers and centrioles appear.
What is telophase two and cytokinesis two?
The nuclear membranes form again and cleavage occurs each new cell is haploid with a unique combination of chromosomes from the mother and father.
What happens in prophase two?
The nuclear membranes of the haploid cells breaks down and the cells prepared to divide. The centrioles and spindle fibers are present.
Where does spermatogenesis occur?
The testes
What is a somatic cell?
They are also called body cells, they are not passed on to children, and make up body tissues and organs
What are sex chromosomes?
They directly control the development of sexual traits
What are homologous chromosomes?
They have the same structures, for each pair of chromosomes one comes from each parent, and has the same genes but codes for different traits
Somatic cells
all the cells of your body except your sex cells
Haploid
an organism or cell having only one complete set of chromosomes, half of a diploid
Diploid
an organism or cell having two sets of chromosomes or twice the haploid number
Autosomes
chromosomes that are not directly involved in determining the sex of an individual
Homologous Chromosomes
chromosomes that have the same sequence of genes, that have the same structured, and that pair during meisosis
Which female organ has the same embryonic origin as the penis?
clitoris
Mitosis results in...
diploid cells (2n)
uterus
environment for developing embryo and fetus
semen
fluid mixture of sperm and supporting materials
Fertilization
fusion of male and female gametes
Meiosis results in...
haploid cells (n)
Mitosis
homologous chromosomes never pair up
labia majora
large folds of tissue covering the inguinal area
vagina
muscular tube for the passage of menstrual flow, copulation, and birth of offspring
how many eggs are produced as a result of one meiotic series of cell divisions?
one
Sex Chromosomes
one of the 23 pairs of chromosomes in the human, contains genes that will determine the sex of the individual, X and Y
testes
pair of reproductive organs in males
Which of the following cells in spermatogenesis is diploid?
primary spermatocyte
oogenesis
process of producing haploid eggs
spermatogenesis
process of producing haploid sperm
Gametogenesis
production of gametes
Gametogenesis
production of gametes through meiosis and other changes
Sexual reproduction
reproduction involving the union or fusion of a male and a female gamete
Gametes
reproductive cells, have only half the number of chromosomes as body cells. Haploid
scrotum
sac containing testes; exterior to the body
bulbourethral gland
secretion that cleanses the urethra prior to ejaculation
seminal vesicle
secretory accessory gland in males; contributes to semen
Most of the bulk of semen is made by the ________.
seminiferous tubules
Sperm are produced in the ________.
seminiferous tubules
clitoris
sensory structure in females; stimulated during sexual arousal
seminiferous tubule
site of sperm production in testes
labia minora
smaller folds of tissue within the labia majora
prostate gland
structure that is a mixture of smooth muscle and glandular material and that contributes to semen
Egg
the female gamete
Sperm
the male gamete
Meiosis
two cell divisions while mitosis has one
Which female organ has an endometrial lining that will support a developing baby?
uterus
What happens in telophase one and cytokinesis one?
A cleavage furough forms and cytokinesis separates the cells. Each cell is now haploid, but the chromosomes are still duplicated.the nuclear membrane forms.
Why do polar bodies die?
Because of unequal division of the cytoplasm
Diploid
Body cells that have two copies of chromosomes one from the mother and one from the father
Polar Bodies
Byproduct of meiosis, cells with little more than DNA that are eventually broken down.
What is metaphase two?
Chromosomes line up on the equator
What are autosomes?
Chromosomes that contain genes and aren't related to the gender of the organism (the first 22 of 23 pairs of chromosomes)
What is crossing over?
Crossing over multiplies the huge number of different gamete types produced by independent assortment
What does a sperm contribute to the embryo?
DNA
What does the egg contribute to the embryo?
DNA, cytoplasm, and organelles
Abbreviation for diploid? Haploid?
Diploid - 2n Haploid - n
gameotogenesis in females
Eggs contribute DNA, cytoplasm, and organelles to an embryo Meiosis- egg gets
What is the sex of a person with 2 X chromosomes?
Female
Meiosis
Form of nuclear division that divides a diploid cells into haploid cells. Essential for sexual reproduction.
How many spermatids does meiosis produce?
Four
Haploid
Gametes are haploid, they also have one copy of every chromosome, gametes have 22 autosomes and 1 sex chromosome
What are the results of meiosis?
Gametes form and four haploid cells, one copy from each chromosome
What happens in metaphase one ?
Homologous chromosomes line up a crossed from each other one on each side of the equator
What happens in anaphase one?
Homologous chromosomes move away from each other toward the opposite ends of the cell. Sister chromatids remain attached.
How many chromosomes are in a typical human being?
46 (23 pairs)
What is the haploid chromosome number in humans?
23 (Autosomes have numbers 1-22)
During oogenesis how many polar bodies are produced and how many eggs are produced?
3 polar bodies and 1 egg