The Cell Cycle & Mitosis
The ability of organisms to produce more of their own kind best distinguishes living things from ______ ______
Nonliving matter
Reproductive cells (sperm and eggs) are called _______
Gametes
Prokaryotes reproduce by ______ ______
Binary fission
______ cells don’t respond normally to the body’s control mechanisms
Cancer
What type of reproduction is characterized by two parents giving rise to offspring that have unique combinations of genes inherited from the two parents?
Sexual
In meiosis (I/II) homologs pair up and separate, resulting in two haploid daughter cells with replicated chromosomes
I
Homologous pairs of chromosomes orient randomly at metaphase I of meiosis. This is known as?
Independent assortment
______ repeats a segment
Duplication
What ratio do Mendel's observations approach as the number of observations get larger and larger?
3:1
Each pair of alleles segregates independently of each other pair of alleles during gamete formation. This is known as?
The Law of Independent Assortment
Nuclear envelope fragments. Microtubules of the mitotic spindle attach to chromosomes. What phase of mitosis is this?
Prometaphase
Joined copies of the original chromosome are called ______ _______
Sister chromatids
In binary fission, the chromosome replicates beginning at the ______
Ori
A normal cell is converted to a cancerous cell by a process called _________
Transformation
An ordered display of the pairs of chromosomes from a cell is called a ________
Karyotype
Meiosis II is also known as _________ division
Equational
For humans there are more than _____ million possible combinations of chromosomes for a single gamete
8
An aneuploid condition that results from three copies of chromosome 21 (AKA Trisomy 21)
Down syndrome
_______ alleles may mask the presence of the ______ allele
Dominant; recessive
Genes located near each other on the same chromosome tend to be inherited together. These are called?
Linked genes
Multicellular eukaryotes depend on cell division for?
Development from a fertilized cell, growth, repair
What attaches sister chromatids along their lengths?
Cohesins
Prokaryotic cells _____ undergo mitosis
Masses of abnormal cells within otherwise normal tissue are called ________
Tumors
The first diploid cell in reproduction is called the _______
Zygote
In meiosis (I/II) sister chromatids separate
II
Any sperm can fuse with any ovum. This is called?
Random Fertilization
_______ syndrome is the result of an extra chromosome in a male, producing XXY individuals
Klinefelter
The two alleles for a heritable character separate (segregate) during gamete formation and end up in different gametes. This is known as?
The Law of Segregation
The probability of one event and another event occurring is found using the _______ rule
Th life cycle of a cell from formation to its own division is called the _____ _____
Cell cycle
The narrow “waist” of the duplicated chromosome, where the two chromatids are most closely attached is called?
Centromere
What does the G1 checkpoint check?
Checks if the DNA is damaged
_______ tumors invade surrounding tissues and can spread to other parts of the body
Malignant
______ is the fusion of gametes
Fertilization
At the start of prophase I, homologous chromosomes align next to each other to form a _________
Tetrad
With both independent assortment and random fertilization, there are about ______ trillion diploid combinations for a zygote
70
Females have three X chromosomes; may be taller than normal but few/no other symptoms for ~75% of people. This is called?
Triple X syndrome (trisomy X)
Possible combinations of sperm and egg can be shown using a _______ _______
Punnett square
______ dominance occurs when phenotypes of the heterozygote and dominant homozygote are identical
Complete
Most cell division results in daughter cells with _______ genetic information (DNA)
Identical
The division of the genetic material in the nucleus is called?
Mitosis
The activity of a cyclin-dependent kinase rises and falls with changes in concentration of ______
Cyclin
Spreading cancer cells to other parts of the body is called _____
The zygote produces somatic cells by _________ and develops into an adult
Mitosis
When does crossing over occur?
Prophase I
The number of complete sets of chromosomes in an organism is called?
Ploidy
A child is born with a small head (microcephaly), unusual features, and has a catlike cry. What syndrome does the child likely have?
Cri du chat ("cry of the cat")
An organism with two identical alleles for a character is _______ for the gene controlling that character
Homozygous
The probability of one event or another event occurring is found using the _______ rule
Addition
Chromosomes align in the middle of the dividing cell. What phase of mitosis is this?
Metaphase
The division of the cytoplasm is called?
Cytokinesis
What does the M checkpoint check?
Checks if all the chromosomes are attached to the spindle
What is the scientific study of heredity and variation?
Genetics
Animals tend to spend most of their life as _______ organisms
Diploid
In what phase of meiosis do the chromosomes (tetrads) move to the center plane of the nucleus?
Metaphase I
Having more than two complete sets of chromosomes is called?
Polyploidy
The "______" hypothesis is the idea that genetic material from the two parents blends together
Blending
An organism's physical appearance is known as its _______
Phenotype
The phenotype of F1 hybrids is somewhere between the phenotypes of the two parental varieties. This is an example of?
Incomplete dominance
All the DNA in a cell constitutes the cell’s _______
Genome
What occurs in the mitotic phase?
Mitosis and cytokinesis
p53 regulation is used at the _____ checkpoint
G1
_______ is the transmission of traits from one generation to the next
Heredity
What is the name of the life cycle that can be found in plants and some algae?
Alternation of generations
Homologous chromosomes separate. Centromeres do not split. This describes what phase of meiosis?
Anaphase I
Pairs of homologous chromosomes don't separate normally during meiosis. This is called?
Nondisjunction
A heritable feature that varies among individuals is called a ______ (today it's called a gene)
Character
An organism that has two different alleles for a gene is ________ for the gene controlling that character
Heterozygous
Two dominant alleles affect the phenotype in separate, distinguishable ways; both alleles are expressed. This is an example of?
Codominance
What is loose DNA + Proteins called?
Chromatin
What occurs during interphase?
Metabolic activity, cell growth, copying of chromosomes, preparation for cell division (G1, S, G2)
What does the G2 checkpoint check?
Checks if the DNA is replicated
What is demonstrated by the differences in appearance that offspring show from parents and siblings?
Variation
Fungi and some protists spend most of their life as _______ organisms
Haploid
_______ are the original source of genetic diversity
Mutations
An abnormal number of a particular chromosome is called?
Aneuploidy
The "_______" hypothesis is the idea that parents pass on discrete heritable units (genes)
Particulate
An organism's genetic makeup is known as its _______
Genotype
Most genes exist in populations in more than two allelic forms. This is known as?
Multiple alleles
What is a package of condensed DNA + Proteins called?
Chromosomes
What happens during S phase?
Synthesize/duplicate DNA
______ plays a key role in the G2-M transition
MPF (maturation promoting factor/M-phase promotion factor)
Units of heredity that are made up of segments of DNA are called?
Genes
What process reduces the number of chromosome sets from diploid to haploid?
Meiosis
Different versions of genes are called _______
Alleles
_____ removes a chromosomal segment
Deletion
Each variant for a character is called a ______ (today it's called an allele)
Trait
Breeding a mystery individual with a homozygous recessive individual is known as a?
Testcross
A gene has multiple phenotypic effects. This is known as?
Pleiotropy
Nonreproductive body cells are called _______ cells
Somatic
Chromosomes condense. Centrosomes radiate microtubules and migrate to opposite poles. What phase of mitosis is this?
Prophase
Signals to divide that come from within the cell are _______
Endogenous
Each gene has a specific location on a certain chromosome. What is this location called?
Meiosis results in _____ daughter cells
4
The centromere of each chromosome splits. The chromosomes are pulled toward opposite poles. This describes what phase of meiosis?
Anaphase II
Translocation
Plants that produce offspring of the same variety when they self-pollinate are known as?
True-breeding
A cross between individuals that are heterozygous for one character is called a _______ cross
Monohybrid
Traits that depend on multiple genes combined with environmental influences are called _______
Multifactorial
Sister chromatids separate and travel to opposite poles. What phase of mitosis is this?
Anaphase
Nuclear envelope reforms and chromosomes decondense. What phase of mitosis is this?
Telophase
Give an example of an exogenous signal
Hormones, growth factors, density-dependent inhibition, anchorage dependence
What type of reproduction is characterized by a single individual passing genes to its offspring without the fusion of gametes?
Asexual
Meiosis I is also known as _________ division
Reductional
Crossing over produces ________ chromosomes, which combine DNA inherited from each parent
Recombinant
_______ reverses orientation of a segment within a chromosome
Inversion
In a process called _______, Mendel mated two contrasting, true-breeding varieties
Hybridization
The phenotypic ratio for a dihybrid cross is?
9:3:3:1
Cystic fibrosis and sickle-cell disease are examples of what inheritance pattern?
Pleiotropy