Psychology Chapter 3 - Genetics and Prenatal Development

genetics

characteristics that are inherited and have been triggered by the genetic sequence inside your cells

genome

unique set of instructions that includes everything a cell may need to create all your body parts, maintain them, and how to die

chromosomes

23 pairs of long molecules of DNA; the 46 chromosomes are where the instructions are packed

deoxyribonucleic acid (DNA)

Spiral or helix shaped structure made up of paired chemicals that carries genetic code

Mitosis

Cell division creating two identical cells

genes

sections of DNA that create particular proteins and have different forms called alleles

alleles

genes that have different forms

phenotype

Your individual, observable characteristics

genotype

the genome that contributes to your phenotypes; are directly linked to changes in your phenotype

epigenome

controller of the genetic expression of a cell

ovum

egg cell that is produced by the female reproductive system

sperm

male gamete; fertilizes the ovum

meiosis

a form of cell division that creates the gametes (sperm + ovum cell)

zygote

a fertilized egg; a new human cell with 46 chromosomes in 23 pairs

sex chromosomes

the 23rd pair of chromosome that determines the sex of an individual; men - XY, women - XX

recessive inheritance pattern

A type of genetic inheritance for single-gene conditions. In order to develop a recessive condition, you must have two of the disease-carrying alleles.

dominant inheritance pattern

A type of genetic inheritance for single-gene disorders. A person with a dominant condition may have just one of the disease-carrying alleles.

polygenic

genetic characteristics that require a trigger or specific influence from the environment to be expressed

multifactorial

Traits that are influenced by both multiple genetic and environmental factors.

Down Syndrome

a condition of intellectual disability and associated physical disorders caused by an extra copy of chromosome 21. (may impair muscle tone and cardiovascular development)

Germinal Stage

1st stage; single-celled zygote divides and implants into the uterus in the first week of development

Embryonic Stage

weeks 2-8; embryo develops the major parts of its body (legs to brain)

Fetal Stage

9 weeks-birth; fetus looks like a baby and adds pounds, organs and brain structures that will allow it to survive on its own

InVitro Fetilization (IVF)

doctor combines the egg and the sperm outside the body in a hospital laboratory then places the resulting zygotes into the uterus where the baby can develop

blastocyst

during germinal stage; ball of cells that becomes larger, then separates into an outer layer mass, replicating until > 150 cells

placenta

~2 weeks after fetilization; organ that allows energy and waste to be transferred between the parent's body and the developing embryo through the umbilical cord

neurons

nerve cells

myelin

a fatty substance that encases and allows for neurons to sense and SPEEDS UP communication

birth defects

major differences/abnormalities in the body or brain present at birth of the baby

age of viability

the age at which a baby can survive in the event of a premature birth; 23 WEEKS!

teratogens

agents, such as chemicals and viruses, that can reach the embryo or fetus during prenatal development and cause harm

cesarean section

surgical procedure that involves makinga small cut into the abdominal wall and uterus to deliver a fetus physically

premature

birth occurs less than 35 weeks after fertilization; occurs in roughly 13 million births globally

low birthweight (LBW)

born after 35 weeks; baby weighs below 2,500g or ~5 1/2 lbs

small for gestational age (SGA) / small for date

baby made it full 9 months but born smaller than expected for their level of development

kangaroo care

treatment for preterm infants that involves skin-to-skin contact; proven to reduce infant mortality rates, improve relationships and accelerate growth

Apgar test

quick medical evaluation of baby's breathing, activity, responsiveness, and heart rate; scale of 0-2 points PER category; > or = to 7 is healthy; < or = 5 is risk

reflexes

automatic motor responses to stimuli that help babies adjust to the world

Rooting reflex

2-3 months; new born cheek is touched, the baby will respond by turning head and preparing mouth for feeding

Moro reflex

5-6 months; newborn feels they are falling, the baby will respond by flailing their arms in and out suddenly

Babinski reflex

disappears by 12-24 months; run finger along newborn's foot, the baby will respond by fanning toes out