Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Foundations of Medicine > Embryology > Flashcards

Embryology Flashcards

1
Q

Key terminology

Gamete

A

Mature haploid male or female germ cell which is able to unite with another of the opposite sex in sexual reproduction to form a zygote

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Key terminology

Embryonic period

A

weeks 3 - 8 in humans (most critical period in terms of risk of teratogens as most major stuctures developing at this time)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Key terminology

Teratology

A

the study of abnormal development

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Key terminology

Teratogen

A

cause irreversible, deleterious structural malformations in fetuses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Key terminology

Mutagen

A

cause changes (mutations) in the genetic material of cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Key terminology

Malformations

A

complete or partial absence of a structure or alterations in its normal configuration can be caused by environmental and/or genetic factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Key terminology

Disruption

A

morphological alterations of already formed structures and are caused by destructive processes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Key terminology

Deformation

A

Abnormal formation due to mechanical factors over a prolonged period

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

List the 7 Phases of embryogenesis

A
  1. Gametogenesis
  2. Fertilisation
  3. Cleavage
  4. Gastrulation
  5. Embryonic folding (morphogenesis)
  6. Organogenesis (3-8 week)
  7. Foetal period
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe Gametogenesis

A
  • Formation of gametes from primordial germ cells (consists of mitosis and meiosis leading to genetic variation)
  • Spermatogenesis -males
  • Oogenesis - females
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe Spermatogenesis

A
  • formation of male gametes
  • Whole process 64-74 days and produces 300 million sperm cells per day
  • Occurs at puberty and continues throughout life
    Phases:
    Spermatogonial phase
  • spermatogonium cells divide by mitosis to form primary spermatocytes
    Spermatocyte phase
  • Primary spermatocytes undergo meiosis forming secondary spermatocytes and then secondary spermatocytes undergo meiosis II to form spermatids
    Spermatid Phase
    -spermatids differentiate into spermatozoa with specific morphology
  • Spermatagonium found nearer to periphery of gonads and move towards lumen as they mature to from spermatids.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe Oogenesis

A
  • Formation of female gametes
  • Starts in development and ends at menopause
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe Fertilisation

A

Union of gametes:
* Fusion of sperm and oocyte to form a zygote (single cell embryo, diploid and sex determined)
* Takes place in the ampulla of the uterine tube

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe Cleavage

A
  • Period of rapid mitotic cell division with no increase in size or volume as cells are confined within the ZP the embryo will change shape (compaction)
  • Daughter cell= blastomere
  • Formation of morula (16+ cells) then blastocyst (200-300 cells)
  • Cells maximize available space by coming into closer contact with each other
  • Inner cells form cell junctions, outer cells form gap junctions
  • Fluid enters through ZP producing a blurred cell mass - signals the formation of the blastocyst
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe Gastrulation

A
  • Formation of the germ layers - ectoderm, mesoderm, endoderm (in order from out to in)
  • Body axis established
  • Embryo goes from a 2 layered structure to a 3 layered structure (end of week 2- start of week 3)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe Embryonic folding (morphogenesis)

A
  • Formation of the body plan
  • Tube within a tube
  • Cranial and lateral regions on Day 22
    Caudal region on Day 23
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Describe Organogenesis

A
  • (3-8 week)
  • Formation of Organs and Organ Systems
  • Basis of these all in place by end of embryonic period
  • Will continue to develop through foetal period
18
Q

Describe the Foetal period

A
  • From week 9 until birth
  • Growth, weight gain:
  • Mainly grows in length during 2nd trimester
  • Most weight is added in 3rd trimester
  • 14g (end of 2nd month) to 3500g (at birth)
  • Tissues mature and become functional
  • Overt sexual differentiation
  • Bone laid down; connections made in CNS
19
Q

List 6 Primary Developmental Processes

A
  1. Cell Division​
  2. Differentiation
  3. Cell Attachment​
  4. Apoptosis
  5. Induction
  6. Cell migration
20
Q

What is Cell division?

A

increase in number of cells influences the shape and growth of embyro

21
Q

What is Differentiation?

A

change in appearance or structure of cells allows for adoption of new functions

22
Q

What is Cell attachment?

A

physical/functional linkages between cells formation of tissue

23
Q

What is Apoptosis?

A

programmed cell death. creates spaces and cavities

24
Q

What is Induction?

A

ability of one cell type to cause another to differentiate, directly or at a distance

25
Q

What is Cell migration?

A

movement from one location to another

26
Q

List the 3 Secondary processes of embryonic development

A
  1. Axis formation
  2. Folding/rotation
  3. Increase/decreases in mass or dimension
27
Q

Describe the Basic Chromosome Theory of inheritance

A
  • 23 pairs to form diploid number of 46 chromosomes
  • Female XX and male XY
28
Q

List Anatomy terms for feotus

A
  • Cephalic/cranial - superior
  • Caudal - inferior
  • Ventral - anterior
  • Dorsal - posterior
  • Rostral - anterior of head
  • Caudal - back of head
29
Q

List anatomical planes of a feotus

A
  • Frontal/coronal plane splits embryo in ventral and dorsal aspect
  • axial/transverse plane splits embryo into cephalic/cranial aspects
  • Saggital plane spits embryo into a right and left side
30
Q

Describe the 4 stages of Fertilisation

A
  1. Sperm binds to zona pellucida glycoprotein
  2. Acrosomal enzymes released from sperm head; sperm digests its way into egg
  3. Egg and sperm plasma membranes fuse and sperm contents enters the egg
  4. Sperm entry triggers completion of meiosis 2 and release of cortical granules by oocyte (make ZP impenetrable to other sperm)

OCCURS IN AMPULLA

31
Q

Name the different parts of the blastocyst and what they give rise to

A
  • Outer cell mass (trophoblast): contacts with the endometrium of the uterus to facilitate implantation and the formation of the placenta
  • Inner cell mass (embryoblast): responsible for the formation of the embryo itself
32
Q

Where in the uterus does the embryo normally implant?

A
  • Implantation (day 6-8) typically occurs in posterior wall of the uterine cavity
  • Abnormal implantation site= ectopic pregnancy
33
Q

Describe the changes in the trophoblast and embryoblast during implantation

A
  • Day 7
  • Trophoblast divides into cytotrophoblast (individual cells) and syncytioblast (single multinucleated cell which produces hCG)
  • Embryobast divides into epiblast (dorsal surface) and hypoblast (ventral surface)
34
Q

Describe day 8-9 of embryo developement

A
  • Formation of 2 cavities = amniotic cavity (epiblast) and primitive yolk sac (hypoblast)
  • Implantation complete
35
Q

Describe day 10-12 of embryo developement

A
  • Uteroplacental circulation established
  • Extraembryonic mesoderm develops then degenerates, forming chorionic cavity
36
Q

Describe day 13 of embryo developement

A

Formation of secondary yolk sac, connecting stalk, and chorionic cavity

37
Q

Name the layers of the trilaminar embryo

A
  1. ectoderm
  2. mesoderm
  3. endoderm
38
Q

State the major tissues derived from the Ectoderm

A
  • Epidermis of skin, hair, nails
  • Nervous system
39
Q

State the major tissues derived from the Endoderm

A
  • Lining of gut tube
  • Lining of respiratory tract
  • Lining of bladder and urethra
40
Q

State the major tissues derived from the mesoderm (Paraxial/ Intermediate)

A
  • Paraxial mesoderm: axial skeleton, skeletal muscle
  • Intermediate mesoderm: urogenital systems
41
Q

State the major tissues derived from the mesoderm (lateral plate)

A
  • Somatic layer: dermis, lining of body wall, parts of limbs
  • Visceral layer: cardiovascular system, mesothelial covering of organs, smooth muscle
42
Q

What is the Notochord?

A
  • Cellular rod
  • Serves as longitudinal support
  • Crucial for signalling that transforms unspecialised embryonic cells to definitive tissues and organs
  • Becomes the nucleus pulposus

Foundations of Medicine (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions