Sac 1 Semester 2 Flashcards
Trimester
A section of pregnancy that is defined by developmental milestones
Zygote
A diploid cell resulting from the fusion of an ovum and sperm
Blastocyst
A cluster of 64 cells where some cells differentiate
Embryo
A developing baby during the second to eight week of pregnancy
Birth process ( 3 stages )
1- Dilation of the cervix -
known as labour
muscles of the uterus wall start to contract
Baby’s head on cervix triggers oxytocin release
2- the birth -
Cervix is fully dilated (10cm) until delivery of baby
3- the afterbirth -
Expulsion of placenta
prenatal development (3 stages)
Germinal - (0-2 weeks)
fertilisation ➡️ implantation
Zygote travels down the Fallopian tube whilst dividing, forms morula then forms a blastocyst which becomes the embryo and placenta.
Embryonic - (3-8 weeks)
Implantation ➡️ 8th week
cells differentiate, taking on specific roles such as skin, heart, bone. Most critical stage as the embryo is susceptible to teratogens and all vital organs form. Limbs start to grow. Risk developing genetic malfunctions, ectopic pregnancy.
Foetal - (9 - 38 weeks)
9th week ➡️Birth. Baby grows from a few centimetres to 50 Rapid growth, body systems mature and begin to function, the placenta is functioning by week 14
Conception
When the sperm and egg meet in the Fallopian tube and form a zygote
Role of the placenta
The placenta is located in the uterus, connected to the baby via umbilical cord
Role is to deliver oxygen nutrients and hormones and remove carbon dioxide and waste
Hormones include : oestrogen and progesterone
And HCG acts as a pregnancy signal by maintains progesterone production
Morula
A solid ball of 16 cells, created from a zygote
Cell differentiation
When cells take on specialised roles. Eg when a blastocyst inner cells become the embryo and the outer cells become the placenta
Apgar scale
Assessment to evaluate the newborns condition :
Appearance Pulse Grimace (reflexes) Activity Respiration
Endometrium
Mucous membrane lining the uterus, where implantation of embryo occurs
Implantation
The attachment of a blastocyst to the uterine wall
Amnion
The innermost membrane that encloses the embryo (thin)
Chorion
The outermost membrane that encloses the embryo
Foetus
The developing baby within the 9- 38 weeks
Umbilical cord
A flexible cord like structure containing blood vessels, attaching mother to the foetus
Teratogens
An agent or environmental factor which causes a malformation of an embryo (e.g tobacco and alcohol)
Neonate
A newborn child less than 4 weeks old (28 days)
Adaption
The process of change by which an organism or species becomes better suited to its environment
Apgar scale
Appearance pulse grimace activity respiration. It is an assessment to evaluate a newborns condition
Reflex
An action that is performed without conscious thought as a response to a stimulus
Fontanelles
The spaces between the bones of a skull in an infant or foetus where ossification isn’t completed
Folate
Folate required for : Red blood cell formation DNA synthesis Cell growth Nervous system development
Prevents Spina bifida
Iodine
Mineral requires for
Promotion of optimal brain development
Promotion of nervous system development
Prevents stumped growth and intellectual disability
Drug and alcohol
Causes (alcohol foetal syndrome) Damage to cns of baby Mental retardation Reduced blood flow to placenta Risk of premature birth Reduced growth
Vaccinations
Rubella : can cause defects in brain, heart, lungs
Chickenpox : defects in eyes, skin and brain
Measles : risk of miscarriage, premature or still birth
Whooping cough : can cause pneumonia, seizures, death of baby
Gestational diabetes
Placental hormones can block the mothers insulin action.
Risk factors are
older mothers
obesity
Family history
Risks : stillbirth, hypertension, miscarriage
Low birth weight
Less than 2.5 kg
Babies can develop severe disabilities
Risk factors : multiple pregnancies and premature birth.
