Unit 6 Lecture Flashcards
Define mitosis
For growth and repair, turning a diploid cell into two identical diploid cells
How many pairs of chromosomes do we have
23
Define meiosis
Production of gametes, one diploid cell produces 4 diploid s at a time
Where does meiosis occur?
Happen in the ovaries or testes
Define dimorphic
Meaning two sexes
What do male and female gonads produce?
Male gonads = testes = sperm
Female gonads = ovaries = eggs
What causes the production of gametes?
Hormones
Where does sex cell production occur?
In útero
How many chromosomes do diploid cell have?
46 chromosomes
How many chromosomes did haploid cells have?
23 chromosomes
What are oogonia
Germ cells for females
What are spermatogonia
Germ cells for males
Get unit two notes for mitosis
What is happening during prophase 1?
The chromosomes from mom and dad get close and perform a cross over to increase genetic diversity
What is primary gamete
Duplicated Diploid cells with 46 chromosomes
What is secondary gamete
Haploid cells with 23 chromosomes and need of one more round of duplication
What is final stage gamete?
A Haploid cell with 23 chromosomes that have a single copy of each chromosome(chromatids
How many sperm are produced from a spermatocyte
1 spermatocyte = 4 sperm
What is the timing for males gametogenesis
Before birth immature lots of speratogonia are produced through mitosis . At birth production of sperm is quiescent
At puberty spermatogenesis begins again
What is the timing for gametogeneis for females?
Before birth they complete mitotic divisions to create all primary procures (~ 500,000 at birth)
Primary procures go quiescent after duplicating chromosomes
At puberty 1 primary procure is chosen for maturation and go through meiosis 1.
Produces a secondary oocyte and first polar body
At 2 nd neurotic division begins where the secondary oocyte stops at the fallopian tube and wait for sperm.
Ovulation occurs
If fertilization occurs one set of chromatids combine with a sperm genome and other is casta away as the 2nd polar bodyv
Define monozygotic twins
Aka identical twins have identical DNA , fertilized by one egg.
Where the zygote splits into two
Define dizygotic twins
Like leia and Luke Aka fraternal twins have different DNA , two separate eggs produced during one ovarian cycle and ultimately fertilized by genetically different sperm
Define nondisjunction
When a gamete end with more or less than 23 chromosomes
What is klinefelters syndrome
Chromosomes in male are XXY causing problems with small testicles, ⬇️ fertility
Define Turner’s syndrome
Chromosome is only X, infertile & short in stature
What hormones are released by hypothalamus
Gonadotropin releasing hormone
What hormones are released by anterior pituitary gland
Lutenizing hormone (LH)
Follicle stimulating hormone (FSH)
What does litenizing hormone do?
What do follicle stimulating hormone do?
Examples of steroid hormones
Testerone, estrogens or progesterone that regulate gamete production
Why is cholesterol good?
It helps with production of progesterone, estrogen, testerone
What can testerone be converted into?
Dihydrotesterone
Aroma taste inhibitors
Are meant to inhibit cholesterol which do something for hormone production and fight breast cancer
What are the 3 estrogens?
Estradiol, estriol, esterone
What does estriol do?
Main estrogen that are post puberty but not pregnant
What does estradiol do?
Main estrogen during pregnancy
What function is esterone
Main estrogen after menopause
Tell me the male spermatogensis control
Hypothalamus sends a pulse(every 90 minutes) for GnRH to the anterior pituitary gland .
The anterior pituitary gland release FSH to stimulate Sertoli cells.
Stimulate Sertoli cells stimulate spermatogenesis
Sertoli cells produce androgen binding protein. Which help carry testerone in the blood.
The anterior pituitary gland release LH to stimulate interstitial cells. Interstitial cells produce testerone that bind to androgen binding cells
What are Sertoli cells?
Cells that make up the walls of the semiferous tubules
How many sperm do males make a day?
100-300 million sperm per day after puberty
What is in the head of a spermatozoa made of? Called?
Composed of acrosome and nucleus
What is the head of a mid piece of a sperm
Centrioles and mitochondria
Define gametogenesis
The production of sex cells in both males and females
Define spermatogenesis
Production of sperm cells
Define oogenesis
Production of egg cells
A cell that has two copies of every chromosomes is called?
A diploid
A cell that has only one copy of every chromosome is called?
A haploid
What is a type of cell division that used for growth and repair in tissues?
Mitosis
What is the description of a diploid cell duplicates all its chromosomes and organelles before dividing into two identical daughter cells?
Mitosis
What is a type of cell division that only happens in the ovaries or testes?
Meiosis
What type of cell division starts as a diploid cell and produces 1-4 haploid cells after two rounds of division
Meiosis
How many pairs of chromosomes do diploid cells have?
23
What is the first step of meiosis that includes the germ cell to go through interphase to duplicate all organelles and chromosomes.
Primary gamete
Define crossing over
Process to exchange genes between homologous chromosomes. Occurs during prophase 1
During anaphase 1 homologous chromosomes do what so that each pair get pulled to an opposite side of the dividing cell
Separate .
At the end of meiosis 1 there are two haploid cells that both have a duplicate copy attached. What are these gametes called?
Secondary gametes
During anaphase 2 each sister chromatid will do what? That causes the centromere holding the two identical chromatids together to break
Split
What is the final stage gamete?
Process of meiosis start with one spermatogonium and ÷ into 4 gametes which will mature into sperm
What are polar bodies?
For females the procress of meiosis start with one oogonium and ÷ into only one mature egg. Other three cells containing genetic material will become a polar body and ultimately disintegrate
What is gonadotropin releasing hormone?
It’s released from the hypothalamus in males every 1.5 hours. This hormone triggers the release of two anterior pituitary hormones
What is follicle stimulating hormone?
Hormones from anterior pituitary gland that stimulates servility cells in the testes to produce androgen binding protein, inhibit and paracrine signals needed for spermatogenesis
Where is the gonatroponin releasing hormone released?
Hypothalamus
What is luteinizing hormone
Anterior pituitary hormone that stimulates interstitial cells of leading to produce testerone.
Why is testerone important?
Critical hormone that supports male secondary sex characteristics and aids in sperm production
Tell me about the follicular phase
Part of the menstrual cycle that actually composed of two espérate cycles of events that happen in the ovaries and uterus. The first half of the ovarian sucker 1-14 days is the follicular cycle
During anaphase what hormone is produced by the anterior pituitary gland that stimulates the development of new follicle in the ovaries
Follicle stimulating hormone
As a follicle develops between 5-13 what hormone is secreted higher and higher
Estrogen
Just before ovulation in females there’s in ⬆️ of what hormone that’s released from the anterior pituitary gland
Luteinizing hormone
After ovulation , in the second half of the ovarian cycle during days 15-28 is called the what phase
Literal phase
During the luteal phase what hormone is the dominant ovarian hormone?
Progesterone
What hormone is produced by the corpus luteum which is what remains of the follicle in the ovary
Progesterone
The uterine cycle has three sub phases. This is the cycle is the first of those subphases and is triggered by low levels of estrogen and progesterone. This does not indicate implantation occurred in the previous menstrual cycle.
Menses
What uterine cycle removes old uterine lining during a period of bleeding?
Menses
What is the second uterine phase
Proliferative phase
What section of the uterine sub phase is stimulated by raising estrogen levels from the ovaries. It causes the thickening of the uterine lining
Proliferative phase
What is the third phase of the of the uterine subphase
Secretory phase
What subphase of the uterine cycle is stimulated by high levels of progesterone from the ovaries? It causes an extra thickening of the uterine lining from the Proliferative phase .
Secretory phase
What subphase adds additional thickening of the uterine lining in anticipation of pregnancy along with ⬆️ vascularuzation and deopositing of fuel molecules like glycogen and lipids for a potential embryo
Secretory phase
What is the structure that is an accessory digestive organ? It releases liquid containing digestive enzymes (carbs and lipids) into the mouth during chewing
Salivary glands
What is the muscular tube that transport food from the mouth to the stomach
Esophagus