bio test study guide ch 13-15

the somatic cells of humans have ____ pairs of chromosomes, _____ in total. pairs __ through ___ are autosomes (contains genes not related to gender). the ___ pair are sex chromosomes (contains genes that determine gender)

23, 46, 1-22, 23rd

_______ results from nondisjunction, it's a condition of having an ____ number of chromosomes. _____ is when cells have 3 copies of a chromosome. _____ is when cells only have 1 copy of a chromosome. ______ is a condition in which there are more than two complete sets of chromosomes in an organism (okay for plants, just bigger)

Aneuploidy, abnormal, Trisomy, Monosomy, Polyploidy

human simple dominant trait examples

Cleft chin, Widow's peak, Hitchhiker's thumb, Tongue rolling, Free earlobes, Lip size, Mid-digital (finger) hair

when two gametes fuse during fertilization, the number of ______ is returned to the ____ amount (diploid)

chromosomes, full

males with an extra Y chromosome, XYY, _____intelligence, _____ sexual development, _____ learning disabilities, _____emotional immaturity

Jacob's syndrome (XYY), normal, normal, slight, delayed

_______ is the result of an extra chromosome in a male, producing ____ individuals. These individuals have male sex organs and are tall, but sterile with feminine body contours, partial breast development, poor beard growth, small testicles and a high pitched voice.

Klinefelter's syndrome, XXY

the chromosomal theory of inheritance

Mendelian genes have specific loci (positions) on chromosomes, and it is the chromosomes that undergo segregation and independent assortment. NOT THE GENES ALONE

the syndrome of "X0", immature females, sterile, ___ to ____ mental range

Monosomy X or Turner's syndrome, low, normal

_______ is the formation of eggs (ova) in ovaries. it is a ______ process (embryo to ______). immature eggs do not complete their development for years, even ____ later. cytokinesis is _____ in oogenesis, producing only __ large cell destined to become the egg

Oogenesis, prolonged, menopause, decades, unequal, one,

the ____ gene is located on the Y chromosome, development of testes

SRY

________ is the formation of sperm in testes. it is ______ from _____ to adulthood, cytokinesis is _____, so all 4 products of meiosis develop into sperm.

Spermatogenesis, continuous, adolescence, equal,

Triple X syndrome, Symptoms range from normal female to limited fertility, tall stature, delayed development of certain motor skills, speech and language, and learning disabilities such as dyslexia

Trisomy X

pleiotrophy (cystic fibrosis have both respiratory and digestive problems, siamese cats have abnormal fur pigmentation and crossed eyes caused by one gene, etc)

When a single gene influences many traits (has multiple phenotypic effects)

epistasis

a non-allelic gene can alter the phenotypic expression of another gene, may completely mask that gene

_____ are alternate forms of a gene for a trait found at a specific ____ on a chromosome

alleles, locus

At anaphase II, the ______ of sister chromatids separate and the now separate ______ travel toward opposite poles. They are considered their own, newly formed, chromosomes now - and are called ______ chromosomes.

centromeres, sisters, daughter

Telophase II: again, just like mitosis - in animal cells a contractile ring creates a ____ _____, and in plant cells, a ____ ____ is laid down to form a new cell wall. The big distinction from mitosis that 4____ ____ cells are formed in this stage.

cleavage furrow, cell plate, haploid daughter

asexual reproduction in eukaryotes produces ______, or genetically identical offspring by _____. ______ is when a new individual grows from a projection of the parent. ______ is when a cell divides into two equal daughter cells after replication. _______ is when a piece of the parent grows into a new organism. ________ is when a modified stem of the parent produces new plants. (runners, horizontal stems growing from the parent plant above ground like potatoes/strawberries/aspen trees)

clones, mitosis, budding, binary fission, fragmentation, vegetative reproduction

in _______, both alleles are completely dominant and are both completely ______ (ex: roan)

codominance, expressed

______ linked genes produce offspring that express only the parental types, and recombination frequencies are ____ than 50%. _____ linked genes produce offspring that express mostly parental types.

completely, less, incompletely,

A ______occurs when a chromosome fragment lacking a centromere is lost during cell division. (This chromosome will be missing certain genes.) A _____ occurs when a fragment becomes attached as an extra segment to a sister chromatid. An _____ occurs when a chromosomal fragment reattaches to the original chromosome but in the reverse orientation. In ______, a chromosomal fragment joins a nonhomologous chromosome.

deletion, duplication, inversion, translocation

meiosis makes 4 genetically _____ sex cells called _____. meiosis occurs in ___ organs

different, gametes, sex

a ______ cross is the inheritance of 2 characters. must not be linked on the ____ ______. (F2 offspring always has a 9:3:3:1 ratio)

dihybrid, same chromosome

crossing over frequency is _____ ______ to the _____ between 2 linked genes. The farther apart 2 genes are, the _____ the frequency of recombinants. (more offspring will not resemble parents)

directly proportional, distance, higher

Achondroplasia (autosomal _______ disorder) it's a type of ______. ______ dominants will die. Dwarves have normal size ______ and feet, ______ and chest, but shortened _____ and ______

dominant, dwarfism, homozygous, hands, head, arms, legs

Huntington's disease (autosomal ______ disorder, lethal) it is a _____-acting gene, symptoms usually appear during _____ age, like gradual brain cell ________, mental _____, and _________ movements. defect: inhibition of brain cell _______, on chromosome __.

dominant, late, middle, deterioration, decline, uncontrollable, metabolism, 4,

_____ is 3 copies of chromosome 21

down syndrome

the law of segregation states that

during the production of gametes, the allele pairs (the two alleles for a heritable character) segregate and end up in different gametes so that offspring acquire one factor from each parent.

the law of independent assortment states that (applies only to genes on different, nonhomologous chromosomes)

each allele for a trait segregates into gametes independently of any other alleles, genes for one trait don't follow the genes for another trait into the gametes

the _____ effects the phenotype. nature ___ nurture. hydrangea color depends on ____ of soil, leaves affected by amount of ____, external and internal _____ affects expression of fur color (fox=melanin requires warmth so color in summer/siamese cat=melanin production occurs in cooler regions of body/sea turtles bc warmer temp=female)

environment, and, acidity, light, temperature

example of epistasis

for mice, coat color depends on 2-5 genes. one gene determines pigment color and the other determines if the pigment will be deposited in the hair. The gene for pigment deposition is said to be epistatic to the gene that codes for black or brown pigment IT DOESN'T MATTER IF THE COLOR IS BLACK OR BROWN IF THE MOUSE IS HOMOZYGOUS RECESSIVE FOR PIGMENT DEPOSITION THEN THERE WON'T BE ANY PIGMENT ALLOWED TO BE DEPOSITED IN THE FIRST PLACE

Today, Mendel's "factors" are called ______, sequences of DNA that code for a _____ (or more specifically, a ______) All of an organism's genetic material is called the ______.

genes, protein, polypeptide, genome

exceptions to mendelian genetics are

genomic imprinting and extranuclear gene inheritance

_____ is an organism's genetic makeup. _____ is the expressed physical traits. phenotype is also influenced by the _____ such as the ____ of the soil changing the flower color of hydrangea flowers

genotype, phenotype, environment, acidity

In telophase I, movement of homologous chromosomes continues until there is a ______ set at each pole. Each chromosome consists of linked _____ _____. Cytokinesis by the same mechanisms as mitosis usually occurs simultaneously. In some species, nuclei may reform, but there is no further _______ of chromosomes. Some cells do not form new _____ _______, since those will be degraded during meiosis II anyway.

haploid, sister chromatids, replication, nuclear envelopes

genes are the unit of ____, made up of ______, children inherit genes for particular ________ _______ from their parents, each gene has a specific location called a _____ on a certain chromosome

heredity, segments of DNA, physical traits, locus

The two chromosomes in each pair are called _______ ________, or homologs. (1 set of 23 chromosomes from each parent)

homologous chromosomes

In anaphase I, the ____ _______ separate and are pulled toward opposite poles. Notice that the _____ ______ are still tightly bound to each other - they do not separate at this time, only the homologous pairs. Also, the _____ ______ is officially _______ at this time because each nucleus that forms at telophase I will have _____ the number of chromosomes as the pre-meiotic cell.

homologous pairs, sister chromatids, chromosome number, reduced, half

independent assortment is when ______ pairs _____ line up along the metaphase plate during meiosis ___, ______ of the other pairs. it is a chance as to which one ends up on which side. As telophase I concludes, the chromosomes get "sorted" into ____ _____independently of every other pair. each human gamete contains ___ million possible assortments inherited from mother and father (because 2^23) also, random ____ leads to genetic variation

homologous, randomly, one, independently, daughter cells, 8, fertilization

the offspring of two different true-breeding varieties are called ______. The parental plants are called the __ (_______) _______, and the hybrid offspring are the ___ ________. When the F1 plants self-fertilize or fertilize each other, their offspring are the ___ __________

hybrids, P (parental) generation, F1 (filial) generation, F2 generation

mitosis makes two genetically _____ body cells called _____ cells. mitosis occurs in all other cells of the body

identical, somatic

in ______ dominance, neither allele is completely ____ or ____, the offspring shows a ____ of both parents (ex: pink)

incomplete, dominant, recessive, blend

males are more likely to be affected by x-linked (sex linked) recessive (most sex-linked are recessive) disorders because

males only have 1 X-chromosome so if they receive recessive allele from mother he will express the trait.

polygenic inheritance means that ____ genes contribute to __ ______ trait. aka, an _____ effect of 2+ genes on one _____. this exhibits a wide range of phenotypes (hair color, height, skin color)

many, one phenotypic, additive, character

______ is a cell division that produces 4 cells with _____ the number of chromosomes as the parent cell, __ divisions occur (haploid, 1N)

meiosis, half, 2

At metaphase II, the sister chromatids are arranged at the _____ _____. The kinetochores of sister chromatids face opposite poles.

metaphase plate,

_____ is cell division that produces 2 cells with the ____ number of chromosomes as the parent cell (diploid, 2N)

mitosis, same

human blood types result from ____ _____ (more than 2 alleles exist for a trait) and ______ alleles.

multiple alleles, codominant

homologous chromosomes are ____ the same as sister chromatids. a homologous pair has a total of ____ sister chromatids, two from each homolog. forms a ____

not, 4, tetrad

Cystic fibrosis (autosomal ________ disorder) the most common ______ genetic disease in the U.S. it's a ______ disease, affecting multiple parts of the body including the ______, ____ ______, and the _____. The Cl- (chloride) transport ______ is not made resulting in thick, sticky ______ that clogs up pancreas, lungs, and digestive tract. it is _______, heterozygotes produce both normal cells and abnormal cells that are missing the transport protein.

recessive, fatal, pleiotropic, pancreas, sweat glands, lungs, protein, mucus, codominant,

genomic imprinting (genes located in the ____) is the phenomenon in which the ______ of an allele depends on whether the allele is _______ from the ____ or the ____ parent, either a _____ or ______ allele is inactivated or ______, the zygote only expresses ___ _____ ____, all ______ daughter cells contain that ______. it's critical for _____ ______ A gene on one homologous chromosome is silenced, while its allele on the ____ ______ is expressed. Critical for normal development because embryonic cells require only ____ active copy, otherwise abnormal development like cancer

nucleus, expression, inherited, male, female, paternal, maternal, silenced, that one allele, somatic, imprint, embryonic development, homologous chromosome, one

nondisjunction

pairs of homologous chromosomes do not separate normally during meiosis; one gamete receives both copies of a particular chromosome, the other gamete receives none

karyotype

photo of chromosomes in a somatic cell during metaphase, arranged by length from longest to shortest

sickle cell disease is caused by a ______ mutation; causes red blood cells to be ____ and fragile, a symptom is _____ and ____ in joints and bones. AA is a ____ red blood cell, SS is ____ cells, and AS is both ____ and ____ red blood cell. A and S alleles are _______. Heterozygous individuals are usually healthy, but they may suffer some symptoms of sickle cell anemia.This is why sickle cell disease is considered _______ ______ at the organismal level, but ________ at the molecular level. Heterozygous (AS) individuals are said to be ______of the sickle cell trait. ppl with AS genotype do not develop sickle cell anemia and have less chance of contracting ______if they live in malaria-infected regions. people with the AA genotype (normal hemoglobin) have a greater risk of dying from ______

point, stiff, anemia, crises, normal, sickled, normal, sickle, codominant, incompletely dominant, codominant, carriers, malaria, malaria

Organisms with more than two sets of chromosomes are termed _____ - the condition is called ______ (this is beneficial to plants because bigger fruits like strawberries but in animals it'll usually result in death of embryo)

polyploid, polyploidy

Hemophilia (______ sex-linked disorder)

recessive, absence of one or more clotting factors. the infected suffer prolonged bleeding because a firm clot forms slowly. Individuals can be treated with intravenous injections of the missing protein

Duchenne muscular dystrophy (______ sex-linked disorder)

recessive, due to the absence of an X-linked gene for a key muscle protein, called dystrophin. the disease is characterized by a progressive weakening of the muscles and a loss of coordination

PKU (phenylketonuria) (autosomal _______ disorder) failure of brain cells to develop because of an _______ ___ ______, mutation of a gene on chromosome ____, causing mental ________, lack of normal ___ pigmentation. defect: absent or defective enzyme allows the _________ of phenylalanine in blood. treatment: low ________ diet so no _____-free gum/candy, _____ drinks, or artificial _______.

recessive, error of metabolism, 12, retardation, skin, accumulation, phenylalanine, sugar, energy, sugars

Tay-Sachs (autosomal ______ disorder) it's a heritable _______ disorder; caused by mutation of a gene on chromosome ___. defective ______ (hexosaminidase A) in brain cells, so either _____ or present in ______ amounts, that breaks down a class of _____ (GM2 ganglioside). allowing excessive _______. symptoms are ______ , ______ and deterioration of _____ and _____ functions

recessive, metabolic, 15, enzyme, absent, reduced, lipids, accumulation, seizures, blindless, mental, motor

SCID (Severe Combined Immunodeficiency Disease) (_______ sex-linked disorder)

recessive, primary immune deficiency. usually results in the onset of one or more serious infections within the first few months of life. SCID is often called "bubble boy disease" during the 1970's when the world learned of David Vetter, a boy with X-linked SCID, who lived for 12 years in a plastic, germ-free bubble

color blindness (______ sex-linked disorder)

recessive, red-green, not total

extranuclear (cytoplasmic) genes don't follow mendelian genetics. they ______ themselves. they are ____ distributed to offspring during _____. All mitochondrial genes in mammals are inherited from _____

reproduce, not, meiosis, mothers

linked genes are located on the ____ chromosome. they __ ___ sort independently (don't produce expected results), new phenotypes or _____ are due to crossing over in prophase 1

same, do not, recombinants

fragile x syndrome is from genomic imprinting on ___ chromosomes. it's a _____ _____ _____, the tip of the ____ hangs on by a single thread of ____. imprinting of the ____ allele by the ____ causes the disease. if the x is inherited from the father then the child is ______

sex, hereditary mental disorder, chromosome, DNA, abnormal, mother, normal

sexual vs. asexual reproduction (which involves gametes, what are offspring like, is genetic diversity involved and if not what is maintained)

sexual reproduction has two gametes and asexual has offspring from one parent; sexual reproduction offspring are genetically unique and asexual reproduction offspring are identical; genetic diversity in sexual reproduction and genetic integrity in asexual

heterozygote advantage of sickle cell and cystic fibrosis

sickle cell has resistance to malaria bc reduce infection from malaria parasite, and cystic fibrosis is more resistant to cholera.

During prophase II a _____ apparatus forms, attaches to kinetochores of each ____ ______, and moves them around. Spindle fibers from one pole attach to the kinetochore of one sister chromatid and those of the other pole to the other sister chromatid. Note that there is NO further _______ of the chromosomes - that is, there is NO INTERPHASE II - meiosis STARTS with_____ ______. The chromosomes simply recondense and the nuclear membrane, if present, _______.

spindle, sister chromatids, duplication, duplicated chromosomes, disintegrates

dominance does not mean it is _____ or is _____ the recessive allele, it means that it is the one that is _____. dominant alleles are also not more ______ in populations (5 fingers is recessive, more prevalent than 6 fingers)

stronger, masking, expressed, common,

3 events that are unique to meiosis that occur in Meiosis 1

synapsis and crossing over during prophase 1, tetrads line up at metaphase plate, at anaphase 1 homologous chromosomes separate instead of sister chromatids

In prophase I, the homologous chromosomes pair up to form tetrads in a process called _______. Special proteins bind the homologous pairs tightly together at several points aligning all 4 ______ together. This arrangement allows for a special process to occur called _______ ______. In this the _____ ends of non-sister chromatids intertwine, break, and exchange _____ segments of DNA. This exchange is mediated by ______, and shows up as x-shaped regions called ______. The sister chromatids now have _____ _______- they are no longer identical. After crossing over takes place, spindle fibers attach to the _________ and begin to move the tetrads around.

synapsis, chromatids, crossing over, terminal, equivalent, enzymes, chiasmata, genetic variation, kinetochores,

a ____ reveals if the dominant phenotype is homozygous or heterozygous. if it is heterozygous then some of the offspring will show the recessive characteristic as well

test cross

At metaphase I, the _____ are all arranged at the ____ _______ . The random alignment also increases _____ ______, Microtubules from one pole are attached to the ______ of one chromosome of each tetrad, while those from the other pole are attached to the other.

tetrads, metaphase plate, genetic variation, kinetochore

males and females have the same effective dose of ___ _____ genes due to ____ _____, which is a condensed object which inactivates most of its genes. the Barr body is reactivated in ____ cells that produce ova so female can donate 2 X chromosomes that are fully functional. females are ____, some cells have active _____ X and others have active _____ X (example of calico cats, some express orange allele and some express the non-orange)

x chromosomes, Barr bodies, ovarian, mosaics, paternal, maternal

the fertilized egg is called the ______ and has one set of chromosomes from _______ ________

zygote, each parent