L4 (PART 2): CYCLES AND PATTERNS

Question 1

I’m Basic unit of heredity passed from one generation to the next.

Answer 1

Gene

Question 2

Variant form of gene

Answer 2

Allele

Question 3

Allele can be?
___
___

Answer 3

dominant;
recessive

Question 4

Specific physical location of a gene

Answer 4

Locus

Question 5

Combination of alleles

Answer 5

Genotype

Question 6

Genotypes can be?
__
__
__

Answer 6

homozygous dominant;
heterozygous dominant;
homozygous recessive;

Question 7

Expression of alleles

ex. blue eyes, brown eyes.

Answer 7

Phenotype

Question 8

Study of how genes and traits are pass down from one generation to to the next.

Answer 8

Genetic

Question 9

Created the 3 laws of inheritance

Answer 9

Gregor Mendel

Question 10

What are the 3 laws of inheritance

Answer 10

Law of
Dominance;
Segregation;
Independent Assortment

Question 11

Law of Inheritance:

“When dominant and recessive alleles are both present, the recessive allele is
masked or suppressed. Only one is dominant and will be expressed”

Answer 11

Law of dominance

Question 12

Law of Inheritance:

“Two alleles of an individual separate with an equal probability into gametes.
In addition, two gametes (male and female) fuse to produce a zygote

Answer 12

Law of Segregation

Question 13

Law of Inheritance:

“During gamete formation, alleles for one gene do not affect the alleles for another gene.”

Answer 13

Law of Independent of Assortment

Question 14

Used to help solve genetic problems

Answer 14

Punnett Square

Question 15

What are the 3 Non-Mendelian Genetics

Answer 15

Incomplete Dominance;
Codominance
Pleiotropy

Question 16

Non-mendelian Genetics

Situation where neither allele is fully dominant over the other, resulting in a heterozygous phenotype that is intermediate between the two homozygous phenotypes. F

Example: in a flower species where red (RR) is completely dominant and white (WW) is recessive, a heterozygous individual (RW) may display pink flowers, which is an intermediate phenotype.

Answer 16

Incomplete Dominance

Question 17

Non-mendelian Genetics

situation where neither allele is fully dominant over the other, resulting in a heterozygous phenotype that is intermediate between the two homozygous phenotypes.

Examples: in a flower species where red (RR) is completely dominant and white (WW) is recessive, a heterozygous individual (RW) may display pink flowers, which is an intermediate phenotype.

Answer 17

Partial Dominance

Question 18

Non-mendelian Genetics

The The heterozygote has a phenotype intermediate of the two homozygotes

Answer 18

Incomplete Dominance

Question 19

Non-mendelian Genetics

two alleles are fully
expressed in the
phenotype

example:
white horse + red horse =Roan horse (red and white hair are expressed equally)

Answer 19

Codominance

Question 20

Non-mendelian Genetics

Example of this is ABO Blood Typing System

Answer 20

Codominance

Question 21

Non-mendelian Genetics

A single gene that has a multiple effects on the phenotype

Answer 21

Pleiotropy

Question 22

Polygenic Inheritance

individuals in a population show a wide range of phenotypes, rather than falling into distinct categories.

Answer 22

Continuous Variation

Question 23

In continuous variation,
The __ the number of genes and
environmental factors that affect a trait,
the continuous the variation in
versions of that trait.

therefore, __ proportional.

Answer 23

greater;
more

directly

Question 24

Environmental effects on phenotype:

Rabbit is homozygous for an allele
that specifies a heat-sensitive
version of an enzyme in melanin-producing pathway

Melanin is produced in cooler
areas of body

This is an example of effect of __ on phenotype.

Answer 24

Temperature

Question 25

Environmental Effects on Phenotype:

In Hydrangea macrophylla, action of gene for floral color (pink to blue) is influenced
by ____—pH < 5.5, blue flowers;
soil pH >5.5, pink flowers

Add aluminum sulfate to lower soil pH;
add lime to increase pH; add sodium
carbonate, rainbow colored flowers;
white varieties stay white regardless of
soil pH

Answer 25

soil acidity

Question 26

_____ genes located on the sex chromosomes, particularly the X and Y chromosomes in mammals. These genes exhibit patterns of inheritance that are influenced by the sex of the individual. In humans, sex-linked genes are often associated with traits or disorders that are more commonly expressed in one sex than the other.

Answer 26

Sex-Linked Genes

Question 27

Sex-Linked Genes Example:

A serious X-linked recessive condition which is the
inability of the blood to clot because the gene
does not code for the necessary clotting agents

What condition is this?

Answer 27

Hemophilia A

Question 28

Sex-Linked Genes Example:

Y-linked (Holandric) – genes found
only on the Y chromosome
– Relatively fewer compared with Xlinked
– Ex: presence of long hair in the
external ear (hypertrichosis of
pinnae)
– Will manifest only in males since
they are the ones with the Y
chromosome

What condition is this?

Answer 28

Hypertrichosis

Question 29

Traits that can be expressed
genotypically in the homozygous or
heterozygous conditions but the
expression of dominance is affected by
the sex of the individual involved

Ex: male pattern baldness – dominant in
males in the homozygous or
heterozygous condition, but will only
manifest in females in the homozygous
condition

Answer 29

Sex-Influenced Genes

Question 30

__ genes are located on autosomes (non-sex chromosomes) but are expressed differently depending on the sex of the individual.

These genes may be dominant or recessive, but their expression is influenced by sex hormones or other factors that differ between males and females.

As a result, the same genotype can produce different phenotypes in males and females.

Answer 30

Sex-influenced

Question 31

An example of a __ is pattern baldness in humans. The gene associated with pattern baldness is located on an autosome, but its expression is influenced by hormones such as testosterone.

Baldness is more common and often more severe in males because they have higher levels of testosterone, which can trigger the expression of the baldness gene.

Answer 31

sex-influenced trait

Question 32

In summary, __ are located on the sex chromosomes and show different inheritance patterns between males and females, while ___ are located on autosomes but are expressed differently depending on the sex of the individual.

Answer 32

sex-linked genes;
sex-influenced genes

Question 33

Example of this is presence of long hair in the
external ear (hypertrichosis of
pinnae)

Will manifest only in males since
they are the ones with the Y
chromosome

Answer 33

Sex-Linked Genes

Question 34

refers to the inheritance pattern of traits that are controlled by multiple genes, each contributing a small amount to the phenotype.

Unlike traits controlled by a single gene (monogenic traits), polygenic traits are influenced by the interaction of multiple genes, as well as environmental factors.

Answer 34

Polygenic Inheritance

Question 35

Polygenic traits often result in a continuous range of phenotypes rather than distinct categories. This means that individuals can exhibit a wide spectrum of intermediate phenotypes, with no clear-cut boundaries between them.

Examples of polygenic traits with __ include height, skin color, and intelligence.

Answer 35

continuous variation