1/114
Looks like no tags are added yet.
Name | Mastery | Learn | Test | Matching | Spaced |
---|
No study sessions yet.
is a branch of science that is related to the formation, growth, and development of embryo
Embryology
Embryology begins with? up to?
formation of gametes, fertilization, formation of zygote, development of embryo and fetus to birth.
Importance of Embryology
to understand normal body structure
to know the cause of congenital anomalies
studies various genetics and environmental factors that disturb normal development and produce birth defects.
Includes the main developmental changes occurring before birth,
Prenatal Development
Prenatal development is divided into which periods?
Embryonic period and Fetal period
Begins at fertilization and ends with the end of the 8th week. (called an embryo)
Embryonic Period
Begins at the beginning of the 9th week and ends at birth. (called a fetus)
Fetal Period
the immature ovum, female germ cell.
Oocyte
the mature female germ cell.
Ovum
the mature male germ cell.
Sperm
the fertilized ovum.
Zygote
one cell divides into two cells
Cell Division
Two types of cell division
Mitotic and Meiotic Division
the cell produces 2 cells each, contains 44 autosomes and 2 sex
chromosomes
Mitotic
(reduction) it occurs in the primitive germ cells in the testes or the ovaries, it produces 2 cells each contains 22 autosomes and one sex chromosomes.
Meiotic
the top of the embryo or the head.
Cranial
superior or the head.
Cephalic
inferior or the tail end.
Caudal
back of the embryo.
Dorsal
anterior or the belly side.
Ventral
near to the midline.
Medial
flank side.
Lateral
median or sagittal. (cuts it to left & right)
Longitudinal
Frontal
Coronal
horizontal. (cuts it to superior & inferior)
Transverse
Gametogenesis and Fertilization occurs at?
1 week
Implantation begins when?
Begins one week after fertilization
Development of the Central Nervous System (CNS; brain & spinal cord) occurs at?
3rd week
Embryonic folding occurs at?
4th week
The Bilaminar and Trilaminar discs are supposed to be present before the?
Embryonic folding
It is the production of mature gametes (sperm and ovum) by gonads (testes in males and ovaries in females).
Gametogenesis
are the cells that give rise to gametes (precursors of the gametes)
Germ Cells
They are not considered as somatic cells
Sperm and Egg cells
are fully functional cells (have differentiated and perform specific functions)
Somatic Cells
are progenitor cells (can differentiate to form one or more kinds of cells) that give rise to functional cells (sperm and egg cells) involved that combine to form the embryo).
Germ Cells
Early on in the development of various organisms, the germ cells have been shown to separate from the?
Somatic Cell
Germ cells can only be found in?
Gonads (ovaries in female and testes in males)
Somatic cells can be found in?
All parts of the body including the reproductive system
Germ cells are capable of division through?
Meiosis
They are the only cells in the body that undergo mitosis and meiosis
Germ Cell
Mitosis allows cells to?
increase in number
To give rise to gametes, however, they have to undergo __________ which gives rise to __________
Meiosis which gives rise to haploid cells
They are diploid and only divide through mitosis.
Somatic Cells
cell division in somatic cells plays an important role in?
growth and replacing lost cells
This is the stage of division in which the chromosomal pairs condense and become compact. At this stage, sister chromatids are joined together at the centromere.
Prophase
This stage is characterized by the breaking down of the nuclear membrane as the spindle fibers begin to move to the opposite poles of the cell.
Prophase
By the end of __________, these fibers align the chromatids at the equatorial plane of the cell.
Metaphase
The contracting spindle fibers separate the sister chromatids and pull them towards the opposite poles of the cell. This ensures that each daughter will eventually contain the same number of chromosomes.
Anaphase
A nuclear membrane starts to form around each set of separated chromosomes.
Telophase
the cytoplasm divides through a process known as ___________ thus completely separating the two daughter cells.
cytokinesis
the cells of the body that make up different tissues and organs. They are therefore important because they make up various parts of the body including all the internal organs, the connective tissue, and bones among others.
Somatic Cells
These changes give rise to thread-like structures, hence the process is termed _________ (thread) in distinction to liviiiotl for convenience into four phases.
mitosis
Cells may divide directly by the simple fission of their nuclei and cytoplasm. This rather infrequent process is called?
Amitosis
Amitosis is said by many to occur only in?
moribund cells (approaching death)
Amitosis is the type of cell division demonstrable in the?
epithelium of the bladder
Somatic is derived from the greek word?
Soma which means body
are the body's raw materials — cells from which all other cells with specialized functions are generated.
Stem cells
stem cells come from embryos that are?
three to five days old
stem cells come from embryos that are three to five days old. At this stage, an embryo is called a?
Blastocyst
meaning they can divide into more stem cells or can become any type of cell in the body.
pluripotent stem cells
Parts of a somatic cell
1. Nucleus
2. Nuclear envelope
3. Chromatin
4. Nucleolus
5. Cytoskeleton
6. Microtubules
7. Centrosome
8. Intermediate filaments
9. Microfilaments
10. Plasma membrane
11. Lysosome
12. Golgi apparatus
13. Cytoplasm
14. Mitochondria
15. Vacuole
16. Rough endoplasmic reticulum
17. Smooth endoplasmic reticulum
18. Peroxisomes
are long, multinucleated cells. The membrane of the cell is the?
Sarcolemma
are long, multinucleated cells. The membrane of the cell is the sarcolemma; the cytoplasm of the cell is the
sarcoplasm
are composed of myofibrils which are composed of sarcomeres linked in series.
Muscle Fibers
Muscle fibers are composed of?
Myofibrils
Myofibrils are composed of?
sarcomeres linked in series
Normal cell division in all cells, except germ cells, occurs by 2 mechanical processes that initially divide the nucleus then the cell cytoplasm.
Mitosis
Mitosis produces?
two daughter cells that are genetically identical to the parent cell
segregation of chromosomes and formation of 2 nuclei
Mitosis
splitting of the cell as a whole into 2 daughter cells
Cytokinesis
no. of chromosome of a goat
60
no. of chromosome of a sheep
54
no. of chromosome of a cattle
60
no. of chromosome of a pig
38
no. of chromosome of a cat
38
no. of chromosome of a dog
78
no. of chromosome of a chicken
78
no. of chromosome of a horse
64
Chromosomes dispersed in nucleus
Gene expression
Cytoskeleton and cell organelles - Distributed and functioning
Mitochondria undergo independent proliferation/division
Interphase
Chromosome DNA has been earlier duplicated (S Phase)
Chromosomes begin condensing
Chromosome pairs (chromatids) held together at centromere
Prophase
Which phase does the microtubules disassemble?
Prophase
Which phase does the mitotic spindle begins to form and spindle apparatus?
Prophase
The amphiaster and the chromosomes together constitute a mitotic figure and at the end of the prophase this is called a
Monaster
What divides during prophase?
Centrosome
_________ ______ appear in the cytoplasm about each centriole.
Astral Rays
hey radiate from it and the threads of the central or achromatic spindle are formed between the two asters, thus constituting the _________
Amphiaster
Chromatic network resolves into? then it breaks into?
Spireme then it breaks into chromosomes
Shape of chromosomes?
Rod, Block, U-shaped
anchor the pole end in position
astral microtubules
They are connected to chromosomes
kinetochore microtubules
form the structure of the spindle apparatus
Polar microtubules
Microtubules now enter nuclear region
Nuclear envelope forms vesicles around mitotic spindle
Kinetochores form on centromere attach to some MTs of spindle
Dynamic instability and the capture of chromosomes
Prometaphase
At end of prometaphase chromosomes move to the
metaphase plate
The longitudinal splitting of the chromosomes into exactly similar halves constitutes the ____________
Metaphase
is a spindle-associated protein required for chromosome alignment at the metaphase plate
Astrin
Metaphase ends when
sister kinetochores separate
At this stage the two groups of daughter chromosomes separate and move up along the central spindle fibers, each toward one of the two asters.
Anaphase
Anaphase is alsos called as?
Disaster stage
At this stage, the centrioles may each divide in preparation for the next division of the daughter cells.
Anaphase
is a microtubule-severing complex involved with this stage of microtubule dynamics.
Katanin