3. Biology and Behavior 1/2

Question 1

Genome

Answer 1

The complete set of DNA of any organism, including all of its genes.

Question 2

Genotype

Answer 2

The genetic material an individual inherits - the genes inherited at conception from one’s parents.

Question 3

Phenotype

Answer 3

The observable expression of the genotype, including both body characteristics and behavior. Only some of the genes from the genotype are expressed in the phenotype. Whether or not the genes are expressed in the phenotype, is a function of dominance patterns.

Question 4

Environment

Answer 4

Every aspects of individuals and their surroundings, other than the genes themselves. The eventual outcome of a given genotype is always contingent on the environment in which it develops.

Question 5

Which five relations are fundamental in the development of every child?

Answer 5

1. Parents genotype - Childs genotype
2. Childs genotype - Childs phenotype
3. Childs environment - Childs phenotype
4. Childs phenotype - Childs environment
5. Childs environment - Childs genotype

Question 6

Chromosomes

Answer 6

Molecules of DNA that transmit genetic information. made up of two twisted strands of DNA. The nucleus of every cell in the body contains chromosomes.

Question 7

DNA

Answer 7

Molecules that carry all the biochemical instructions involved in the formation and functioning of an organism.

Question 8

Genes

Answer 8

Sections of chromosomes that are the basic unit of heredity in all living things. The instructions from the DNA are packaged in genes. Each gene is a segment of DNA that is the code for the production of particular proteins.

Question 9

Hvor mange kromosomer har mennesket totalt i hver celle, og hvordan er de strukturert?

Answer 9

Mennesker har til sammen 46 kromosomer, delt inn i 23 par, i kjernen av hver celle (nukleus). Hvert par bærer gener av samme type - altså sekvenser av DNA relatert til de samme trekkene.

Question 10

What are two mechanisms that promote variability among individuals?

Answer 10

Crossing over and mutation.

Question 11

Crossing over

Answer 11

The process by which sections of DNA switch from one chromosome to another.

Question 12

Mutation

Answer 12

A change in a section of DNA. Some mutations are random errors, others are caused by environmental factors.

Question 13

Sex chromosomes

Answer 13

The chromosomes (X and Y) that determine an individuals designates sex at birth. These chromosomes are an exception to the general pattern of chromosome pairs.

Question 14

What combination of the sex chromosomes does a male and female have?

Answer 14

Male: XY
Female: XX

Question 15

Why does the genetically male parent always determine the genetic sex of the offspring?

Answer 15

Since a female does only have X chromosomes, the division of her germ celles will result in all her eggs having an X. However, because a male is the combination of XY, half his sperm will contain an X chromosome and the other half contain a Y.

Question 16

Endophenotypes

Answer 16

Intermediate phenotypes, including the brain and nervous systems, that do not involve over behavior.

Question 17

Regulator genes

Answer 17

Genes that control the activity of other genes (switching on and off).

Question 18

Alleles

Answer 18

Two or more different forms of a gene. The alleles of a given gene influence the same trait or characteristics (e.g. eye color), but they contribute to different developmental outcomes (e.g. brown, blue, green etc.).

Question 19

Dominant allele

Answer 19

The allele that, if present, gets expressed.

Question 20

Recessive allele

Answer 20

The allele that is not expressed if a dominant allele is present.

Question 21

What is the simplest pattern of gene expression, discovered by Mendel?

Answer 21

The dominant-recessive pattern.

Question 22

Homozygous

Answer 22

Having two of the same allele for a trait - the corresponding trait will be expressed.

Question 23

Heterozygous

Answer 23

Having two different alleles for a trait - the instructions for the dominant allele will be expressed.

Question 24

Polygenic inheritance

Answer 24

Inheritance pattern in which traits are governed by more than one gene - many different genes contribute to any given phenotypic outcome.

Question 25

What is an example of a phenotype produced by a genotype-environment interaction, and what is it?

Answer 25

Phenylketonuria (PKU): a disorder related to a defective recessive gene on chromosome 12 that prevents metabolism of the amino acid phenylalanine.

Question 26

Carrier genetic testing

Answer 26

Genetic testing used to determine whether prospective parents are carriers of specific disorders.

Question 27

Prenatal testing

Answer 27

Genetic testing used to assess the fetus risk for genetic disorders.

Question 28

Newborn screening

Answer 28

Tests used to screen newborn infants for a range of genetic and non-genetic disorders.

Question 29

Epigenetic's

Answer 29

The study of stable changes in gene expression that are mediated by the environment. Epigenetic effects, the switching on and off of genes, underlies many aspects of development and individual differences. This process is affected by experience via methylation.

Question 30

Is the genotype "fixed" at conception?

Answer 30

No, although the structure of the genetic code remains "fixed" during ones lifetime, the expression of the genetic code is altered. A specific gene does not lead to a specific phenotype, but instead, the genetic encoding of proteins alters the ways in which genes are expressed as phenotypes.

Question 31

Methylation

Answer 31

An epigenetic mechanism which silences gene expression. Methyl molecules block transcription in the promotor region of the gene, turning off gene activity. Can be seen as a dimmer switch, regulating the amount of protein produced by a given gene.

Question 32

Why is epigenetic processes involving methylation of particular interest to developmental scientists?

Answer 32

Because they provide evidence for long-term epigenetic effects of early adverse experiences on gene expression, impacting later health and well-being.

Question 33

Behaviour genetics

Answer 33

The science concerned with how variation in behavior and development results from the combination of genetic and environmental factors.

Question 34

Heritable

Answer 34

Refers to characteristics or traits that are genetically transmitted.

Question 35

Heritability

Answer 35

A statistical estimate of the proportion of the measured variance on a trait among individuals in a given population that is attributed to genetic differences among those individuals.