Hps202 Week 1

Front 1

DNA (deoxyribonucleic acid)

Back 1

twisted ladder shape containing genes on the rungs

Front 2

Chromosomes

Back 2

Humans have 46 of these

Front 3

Genes

Back 3

The blueprint for our bodies

Front 4

Autosomes

Back 4

The numbered chromosomes

Front 5

Sex chromosomes

Back 5

Consists of an XX in a woman and an XY in a man

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23,000

Back 6

The number of genes in a human

Front 7

Allele (AL-eel)

Back 7

Variations in a gene for a certain characteristic

Front 8

Dominant

Back 8

An allele which will express over other genes

Front 9

Recessive

Back 9

Alleles which only express when they are homozygous

Front 10

Co-dominance

Back 10

Some alleles carry equal weight and express together (as in blood type)

Front 11

Genotype

Back 11

The genes which produce the observable trait

Front 12

Phenotype

Back 12

The observable trait eg blue eyes

Front 13

Genetic mutations

Back 13

Are permanent. Build up in our cells with age.

Front 14

Germ cells

Back 14

Sperm and egg cells

Front 15

Somatic cells

Back 15

All cells in the body, excluding germ cells

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Genetic predisposition

Back 16

An inherited susceptibility to a disease or condition

Front 17

Autosomal recessive genetic disorders

Back 17

Disorders which occur when each parent passes on the same faulty gene to their child

Front 18

Homozygous

Back 18

When the genotype contains identical alleles

Front 19

Heterozygous

Back 19

When the genotype contains different alleles

Front 20

Germinal, embryonic, foetal

Back 20

The three periods of the prenatal phase

Front 21

Germinal period

Back 21

Period from conception to implantation of the zygote by the end of the 2nd week

Front 22

Blastocyst

Back 22

A ball of cells consisting of two layers of cells resulting from rapid cell replication after fertilisation

Front 23

Trophoblast layer

Back 23

The outer cell layer of the blastocyst, enclosing a fluid-filled cavity. It develops into tissues that support, protect and nourish the developing embryo

Front 24

Embryonic disk

Back 24

The inner cell layer of the blastocyst, containing the cells that will become the embryo

Front 25

Implantation

Back 25

Attachment of the blastocyst to the uterine wall six or seven days after fertilisation

Front 26

Amnion

Back 26

A membrane that grows from the trophoblast after implantation. It forms as a sac that fills with fluid from the mother’s tissues (amniotic fluid)

Front 27

Amniotic fluid

Back 27

Fluid that cushions the developing organism from jolts, helps maintain constant temperature and provides support and a medium in which the foetus can move

Front 28

Yolk sac

Back 28

The structure that produces blood cells until the embryo is capable of producing its own

Front 29

Chorion

Back 29

A membrane that forms around the amnion by the end of the second week. This becomes the foetal part of the placenta

Front 30

Placenta

Back 30

A complex organ made up of tissue from both the mother and the embryo that acts simultaneously as a barrier that prevents the bloodstreams of the mother an embryo/foetus from coming into direct contact and as a filter that allows nutrients, oxygen and waste products to be exchanged

Front 31

Allantois

Back 31

The foetal membrane that forms the umbilical cord

Front 32

Embryonic period

Back 32

The period from implantation until about the end of the eighth week of gestation

Front 33

Organogenesis

Back 33

The formation of the basic organs of the body

Front 34

Ectoderm

Back 34

The outer cell layer that will form nervous system, skin and hair

Front 35

Mesoderm

Back 35

The middle cell layer that will form the muscles, cones, circulatory system, & other internal organs

Front 36

Endoderm

Back 36

The inner cell layer that will form the digestive system, lungs, urinary tract and glands

Front 37

Histogenesis

Back 37

The development of function of the organs as they begin to sense, secrete, move etc

Front 38

Trimesters

Back 38

The three periods of three months each into which the nine months of gestation are often divided when discussing prenatal development

Front 39

Teratogens

Back 39

From the greek word teras, meaning ‘monster’. Any agent that causes a birth defect

Front 40

Thalidomide

Back 40

A drug that was prescribed to pregnant women as a sedative and to control nausea in the early stages of pregnancy. It had a teratogenic effect, causing deformities in many foetuses

Front 41

Rubella

Back 41

A viral infection that can cause severe developmental defects in babies born to mothers who contract the disease in the first months of pregnancy

Front 42

Human immunodeficiency virus (HIV)

Back 42

A viral infection that leads to AIDS. About a quarter of pregnant women who are infected with HIV pass it on to their child

Front 43

Rh incompatibility

Back 43

The most frequent and destructive of a number of blood incompatibilities. It occurs when an Rh-negative mother gives birth to an Rh-positive child

Front 44

Foetal Alcohol Syndrome (FAS)

Back 44

A complex of abnormalities found in many children of mothers who drank alcohol heavily during pregnancy

Front 45

Neuron

Back 45

brain nerve cells

Front 46

Neuronal proliferation

Back 46

new brain cell creation

Front 47

Cell migration

Back 47

May be passive or active. Cells move to the correct area

Front 48

Neuronal differentiation

Back 48

Cells become specialised

Front 49

Autonomic functions

Back 49

Bodily functions necessary for life. Includes breathing, eating, sleeping etc.

Front 50

Brain development

Back 50

The process of creating, strengthening and discarding connections.

Front 51

Synapses

Back 51

Form pathways that connect parts of the brain

Front 52

Synaptic pruning

Back 52

Gradual process of discarding unused or unnecessary synapses

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Myelin

Back 53

White, fatty tissue that insulates mature brain cells. Ensures clear transmission across the synapses

Front 54

Myelination

Back 54

The process of myelin forming on axons. Rate and growth affected by experiences

Front 55

Plasticity

Back 55

The brain’s ability to chance in response to repeated stimulation

Front 56

Sensitive periods

Back 56

Windows of time in the developmental process when certain parts of the brain may be most susceptible to particular experiences

Front 57

Implicit memory

Back 57

The ability to perceive the environment and recall it in unconscious ways

Front 58

Explicit memory

Back 58

Conscious memories. Tied to language development. Develops around age 2