1.11 - Normal control of cell growth and differentiation Flashcards
what is hypertrophy
increase in the size of cells, leading to an overall increase in tissue or organ size.
what is hyperplasia
increase in the number of cells within a tissue or organ, leading to an overall increase in size.
What is atrophy
decrease in size or wasting away of tissue or organ due to a reduction in cell size and/or number of cells.
What is hypotrophy
inadequate development or underdevelopment of tissue or organ, usually due to insufficient growth or nutrition.
What is neoplasia
abnormal and uncontrolled growth of cells or tissues, forming a neoplasm (or tumor)
What is apoptosis
programmed cell death process that occurs in a controlled and regulated manner.
e.g interdigital death zone
What is necroptosis
a regulated form of necrosis (cell death) that combines features of both necrosis and apoptosis
traumatic cell death?
5 stages of prenatal development
from cleavage to morula = proliferation BUT no increase in size = so cells get smaller
what is a blastomere
cell produced by the early division (cleavage) of a fertilized egg (zygote) during the early stages of embryonic development.
within the first 30 hours
draw out the 5 stages of pre-embryonic development
from cleavage to morula = proliferation BUT no increase in size = so cells get smaller
structure of the blastocyst after 6 days / 8 days / 2 weeks
note germ layers form after 2 weeeks
what are the primary germ layers
ectoderm
mesoderm
endoderm
define trophoblast / embryoblast / epiblast / hypoblast
trophoblast =outer layer of cells in the blastocyst that will form the placenta
embryoblast =inner cell mass (ICM) of the blastocyst, which will develop into the embryo itself.
epiblast =upper layer of the embryoblast in the bilaminar disc
hypoblast = lower layer of the embryoblast in the bilaminar disc
how do the primary germ layers form
gastrulation
What is gastrulation, and why is it important in development?
process where the blastocyst reorganizes into a three-layered structure, forming the germ layers
Each germ layer gives rise to specific tissues and organs.
crucial for establishing body axes (e.g., anterior-posterior).
how does gastulation occur
epiplast cells migrate over the surface and down into the primitive groove
first replacing hypoblast cells with endoderm
then filling space between epiblast and hypoblast with mesoderm
epiplast will soon become ectoderm
What is neurulation
process by which the ectoderm forms the neural tube, which will develop into the brain and spinal cord.
how does neuralation occur
neural plate folds into neural grove
As the neural folds approach each other, they fuse at the midline, forming the neural tube.
fusion starts in the cervical region (midway along the body axis) and proceeds both rostrally (towards the head) and caudally (towards the tail).
tube give rise to brain (rostral) + spinal cord
neural crest cells = found at edges of the neural folds
they will migrate + form PNS
neural folds close around day 24-26 = then CNS can form
when does neurulation occur
week 3-4
what is the neural plate
a flat, thickened region of the ectoderm.
what are nueropores and function
openings at both ends of the tube
rostral neuropore closes around day 24 to form the brain region.
caudal neuropore closes around day 26 to form the spinal cord region.
when does the body cavity form and what is it called
week 3-4
coelom
what does each germ layer give rise to
ectoderm (formed by gastulation of the epiblast) = nervous system / skin / sense organs
mesoderm (Formed during gastrulation from the epiblast) = musculoskeletal + cardiovasuclar + reproductive
endoderm (gastrulation from the hypoblast) = digestive system / urinary system / endocrine glands
development will be properly covered in 15
okay
