Brainscape's Knowledge GenomeTM

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


See full index

Biology > Patterns of inheritance > Flashcards

Patterns of inheritance Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

Gene

A

Length of DNA which determines the sequence of amino acids in a ppc

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

Locus

A

Position of a gene on a chromosome

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

Allele

A

different form of a gene occupying same position on homologous chromosomes

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

Genotype

A

There combination of alleles present in an organism

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

Phenotype

A

The physical observable characteristics that are expressed in an organism

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

Heterozygous

A

A genotype consisting of two different alleles

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

Homozygous

A

A genotype consisting of two identical alleles

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

Dominant

A

An allele which is expressed in the phenotype irrespective of the other allele present for the gene

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

Recessive

A

An Allele which is masked by a dominant allele and is only expressed when there are 2 recessive alleles present for that specific gene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Multiple alleles

A

When there are 3 or more alleles present for one specific gene e.g. blood group I’A, I’B, I’O

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Co-dominant alleles

A

Both alleles are equally dominant and have an impact on the phenotype in a heterozygote, usually causing an intermediate characteristic.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Pure breeding

A

Genotype is homozygous for characteristic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Homogametic

A

Both sex chromosomes are identical e.g females

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

Heterogametic

A

Both sex chromosomes are different e.g. males

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Monohybrid inheritance

A

Inheritance of a single gene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Test cross

A

The organism of unknown phenotype is crossed with homozygous genotype to determine if an organism is heterozygous or homozygous for that characteristic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Proportion of polymorphic gene loci

A

n of polymorphic gene loci/ total number of loci

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Inversion mutation

A

Segment of chromosomes breaks off and is inserted bit eh same place but in the opposite direction telative to the rest of the chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Insertion mutation

A

-Extra nucleotide is added to DNA sequence
-Frameshift of codons in mRNA
-Leads to altered sequence of amino acids in translation
-Results in a non-functioning ppc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Deletion mutation

A

-Nucleotide is deleted
-Causes frameshift in the codons in mRNA
-Leads to altered sequence of amino acids in translation
-Results in non-functioning ppc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Substitution mutation

A

-Single nucleotide is inserted into the DNA sequence in place of the correct nucleotide
-Different codon
-Could be silent, missense or nonsense

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Translocation

A

Movement of gene fragment from one chromosome location to another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Nonsense mutation

A

Triplet for amino acid is replaced for stop codon- ppc is shortened and does not function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Missense mutation

A

Triplet for amino acid is replaced for a different one. Ppc will probs have a different 1 structure, which will alter 2,3,4.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Silent mutation

A

Triplet for amino acid is replaced with triplet for the same amino acid. ppc remains unchanged

26
Q

Frameshift mutation

A

All triplets are affected- ppc is completely altered

27
Q

Beneficial mutation

A

improved ppc function, natural selection will select individuals with improved protein function, increases the frequency of beneficial allele within the population

28
Q

Cystic Fibrosis causes

A

Recessive allele on chromosome 7 which codes for transporter protein called CFTR
CFTR sits in ccm of cells in alveoli- allows cl ions to pass out of cells

29
Q

CF symptoms

A

Abnormally thick mucus in the lungs and pancreas
Prone to bacterial infections

30
Q

CF treatment

A

-Daily physiotherapy to aid the clearance of mucus as excess mucus traps bacteria and leads to infection
-Administer pancreatic enzymes as mucus blocks pancreatic duct- these aid digestion of lipids and proteins
-Antibiotics to treat bacterial infections
-Males may need fertility treatment as mucus can block sperm ducts
-Maintain childhood vaccines e.g. MMR

31
Q

CFTR normal

A

Transport proteins transport cl ions out of cell
High conc of ions outside cell
Lowers water potential compared to the cell cytoplasm
Draws water out of the cells which dilutes mucus
Makes it thin enough to be moved by ciliated epithelium

32
Q

CFTR with CF

A

Transport proteins do not pump cl ions out of the cell
No water is drawn from the cells
Mucus remains thick and viscous
Ciliated epithelium unable to clear it
Mucus accumulates (goblet cells produce it)
Bacteria get trapped- more likely bacterial infections

33
Q

Phenylketonuria (PKU)

A

Abnormal base sequence of DNA coding for enzyme. Affects single locus on chromosome 12
Sufferers lack essential enzyme phenylalanine hydroxylse
enzyme: phenylalanine -> tyrosine-> melanin

34
Q

PKU symtonms

A

-Lack of PH, lower levels of phenylalanine so fairer skin & hair
-Phenylalanine accumulation in blood- severe brain damage in children
-Mental retardation
-Routine testing at birth- if affected, strict diet without phenylalanine

35
Q

Huntington’s disease

A

-Insertion mutation on chromosome 4
-Autosomal dominant allele
-40+ repeats of CAG: gene stutter
-Caused by accumulation of protein fragments in neurones in brain-> neurone death

36
Q

Huntingtons symptoms

A

Reduced ability to send brain impulses
So, reduced speech, movement, thought processing
Progressive disorder

37
Q

Sickle Cell anaemia

A

-Codominant
-Caused by base substitution mutation at a single locus on chromosome 11
-Valine is substituted in place of glutamic acid
-Affects B globin
-makes little difference when Hb is bound to O2
-RBC become sickle shaped
-Distorted- dec O2 carrying ability, stick in capillaries, prevent normal cells passing

38
Q

SCA symptoms

A

-Severe anaemia, tired easily, breathless easily, can be fatal
-Pain, cramps
-Common in Africa & India- provides resistance to malaria as plasmodium can’t live & reproduce within affected RBC

39
Q

Duchenne Muscular Dystrophy (DMD)

A

Dominant allele carried on the X chromosome
DMD gene codes for a protein called dystrophin required for muscle contraction
Mutations of gene result in non-dystrophin

40
Q

Codominance and blood groups

A

A and B are codominant, O is recessive
A: I’A I’A or I’A I’O
B: I’B I’B or I’B I’O
AB: I’A I’B
O: I’O I’O

41
Q

HLA

A

All cells have antigens on ccm
HLAs are very important in organ transplants
The equivalent of major histocompatibility complex
HLA antigens are coded for by 6 gene loci on chromosome 6
Each HLA gene exhibits codominance. Inherited from parents expressed equally.
Genes for 6 HLAs inherited together so example of genetic linkage

42
Q

Autosomal linkage

A

Non sex chromosomes
Two or more genes that are located on the same chromosome
these alleles are normally inherited together.

43
Q

Autosomes

A

non sex chromosomes

44
Q

Nail Patella Syndrome & blood group
(example of autosomal linkage)

A

non-sex linked- affects males and females equally
-underdeveloped knee caps and nails, inability to stretch elbows
-Dominant
-allele for NPS found on chromosome 9 very close to ABO group gene. So, NPS and blood group gene usually inherited together due to crossing over during meiosis

45
Q

Sex linkage

A

When gene that it codes for is carried on the sex chromosome

46
Q

Haemophilia A

A

-Recessive allele carried on the X chromosome
-Individuals fail to produce clotting factor VII
-Recessive allele expresses altered protein that does not function
-Increases clotting time, internal bleeding etc
-Males only have 1 X chromosome, while females have two copies, this condition is almost always found in males

47
Q

Model organisms- Drosophila

A

-Short life cycle-> large n individuals can be produced in short period of time
-Short regeneration time so many generations can be studied in a short time
-Minimal culturing requirements
-Only 4 pairs of chromosomes- genetic simplicity
-No ethical or moral issues

bad:
-anatomy of the brain and major organs are v different from humans
-lack of in-depth cognitive abilities

47
Q

Dihybrid crossing

A

4x4
The pattern of inheritance of two characteristics which are determined by 2 genes at different loci

48
Q

Dihybrid crossing genotypes vs alleles in gametes

A

Parent genotype: GgRr
Alleles present in gametes: GR, Gr, gR, gr

49
Q

what are chromosome mutations

A

Change in the n of chromosomes, change in structure of chromosomes

50
Q

Translocation

A

Piece of chromosomes breaks off and transferred to another chromosome
e.g. Down’s syndrome. Long arm of chro 21-> chro 14

51
Q

Non-disjucntion

A

when homologous chromosomes fail to separate in meiosis I or sister chromatids fail to separate in meiosis II
Changes diploid n. chromosomes. Gamete has +1 or -1
e.g. DS- 3 copies of chro. 21
Turner’s- single X chro
Klinefelter’s- only affects males. XXY.

52
Q

Parental carrier testing

A

couples risk of having genetic condition assessed by testing for the presence of recessive allele

53
Q

Pre-natal testing

A

embryos tested for chromosome mutations and other inheritable conditions

54
Q

New-born screening

A

babies tested shortly after birth to identify genetic conditions that require immediate treatment

55
Q

Ethical concerns about eugenic screening

A

-may lead to an abortion
-risk of possible damage to embryo
-risk of false positives or negatives
-embryo cannot consent

56
Q

Pedigree analysis

A

Genetic counsellors use family trees to construct pedigree trees to calculate the probability of having a child with the inherited disease

57
Q

Genetic counselling consist of

A

Evaluating family history and medical records
Ordering genetic tests
Evaluating results
Helping parents understand and reach decisions about future
Provide emotional support

58
Q

Ethical dilemmas of genetic counselling

A

-Difficult decisions- abort?
-genetic counsellors may learn sensitive information about family- e.g. father is not the biological father

59
Q

what is the function of HLAs?

A

to help the immune system distinguish the body’s own proteins from proteins made by pathogens

60
Q

state the location of factor viii gene in a cell

A

X chromosome in nucleus

Biology (18 decks)

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