genetics ch. 1,2,3
The visible trait, biochemical change, or effect on health in an individual is called the phenotype all the alleles in a population constitute the
gene pool
all of the alleles in a population
gene pool
altering a gene or genome in a way that does not occur in nature such as giving a rice plant a gene from a daffodil is called
genetic modification
The branch of biology that deals with the variation and transmission of inherited traits are known as
genetics
the study of how traits are transmitted
genetics
The underlying DNA instructions in a cell are referred to as its
genotype
The end result of meiosis in humans is the production of cells that have _____________the amount of genetic material that somatic cells do.
half
Human gametes are _____________, which means that they have only one copy of each chromosome.
haploid
Centenarians have higher levels of ________ _________ _______________than other people, which researchers estimate adds 20 years of life
high-density lipoprotein
In somatic cells, one member of each pair of chromosomes comes from the person's mother and one comes from the father to form chromosome pairs called ______________
homologs
In eukaryotic cells, the chromosomes are enclosed in a membrane-bound structure called the
nucleus
The majority of genes in a eukaryotic cell are found within the
nucleus
Oogenesis begins in a diploid cell called a(n)
oogonium
A phosphate group is a phosphorus atom bonded to four __________ atoms
oxygen
The steps of a DNA double helix hold information because they are:
pairs of four types of bases abbreviated A, T, G, and C.
The use of genetic information to select drugs that will be most effective for a specific patient is called
pharmacogenetics
__________________ helps to select drugs that are most likely to work, specific for an individual patient, least likely to have side effects.
pharmacogenetics
A____________________________ is a fat molecule with attached phosphate groups depicted as a head with two parallel tails
phospholipid
By the tenth week of prenatal development, the ___________ is fully formed. This structure links the woman and her fetus for the rest of the pregnancy.
placenta
Disorders that accelerate aging and shorten life span are called ______________
progeroid
Crossing over occurs in:
prophase 1 of meiosis
Major macromolecules that makeup cells:
proteins, fats, DNA
an example of genetic modification
providing plants with a gene that makes them resistant to insect pests.
After _____________ about once a month, one ovary releases the most mature oocyte.
puberty
In meiosis, the first division is called a(n) ________________ ______________ because it decreases the number of replicated chromosomes from 46 to 23.
reduction division
Sperm cells develop within a 125-meter-long network of vessels called the _____________________ _______________
seminiferous tubules
The ________________ ________________ are the site where sperm cells are produced
seminiferous tubules
One of the functions of saclike organelles is that they
sequester biochemicals that could harm other cellular constitutes
sperm and oocytes fall in the category of _____ ______
sex cells
Without meiosis, the sperm and oocyte would each contain 46 chromosomes, and the fertilized ovum would have twice the normal number of chromosomes to form a genetically overloaded cell called a(n) ________________
polyploid
______________________rapidly and neatly dismantles a cell into membrane-enclosed pieces that a phagocyte can mop up.
Apoptosis
The confirmation that President Jefferson had children with his slave Sally Hemmings was based on DNA analysis of the
Y chromosome
Unlike mitosis, meiosis in humans leads to the production of four genetically- different daughter cells
four genetically different daughter cells
A stem cell divides by mitosis to yield either two daughter cells that are stem cells like itself or one that is a stem cell and one that is a partially _______________ _______________
specialized progenitor
The first cell that leads to the development of new individual forms when a ________ and an ________ join
sperm ; oocyte
The process of the formation of sperm cells, which begins in a diploid stem cell, is known as
spermatogenesis
Carbohydrates: ______________________, Lipids: _________________, Nucleic acids: ___________________
sugars and starches; fats and oils ; DNA and RNA
identify a characteristic of dizygotic twins.
their occurrence runs in families
Functions of organelles:
they dismantle debris, they provide energy, they secrete substances
How many domains of life?
three: Archaea, Bacteria, and Eukarya.
Interphase is divided into ________ (g) phase and __________ (s) phase
two gap phases and one synthesis phase
compares DNA sequences among individuals to establish a rule out identity
DNA profiling
technique that compares DNA sequences among individuals to establish or without identity
DNA profiling
Biologists recognize three major domains of life:
archaea, bacteria, eukarya
Which of the following are current applications for using stem cells?
1. create tissues and organs for use in transplants 2. produce hard-to-culture cells in order to observe the earliest signs of a disease 3. introduce reprogramming proteins to stimulate stem cells in a natural niche 4. discover and develop drugs
In humans, meiosis ensures that the sperm and oocyte each contain ______ chromosomes. Thus, the fertilized ovum would have _____ chromosomes.
23 ; 46
Does the human microbiome consist of which of the following?
Bacterial cells, fungal cells, protozoan cells
__________________ ________________ occurs when the specialization of one group of cells causes adjacent groups of cells to specialize.
Embryonic induction
When is a prenatal human known as an embryo?
First 8 weeks of prenatal development
Following mitosis, the cell enters the ______________ resuming the synthesis of proteins, lipids, and carbohydrates which contribute to building the extra plasma membrane required to surround the two new cells formed from the original one.
G1 phase
Three phases that makeup interphase:
G2 phase, S phase, G1 phase
Which of the following special cells form gametes?
Germlike cells
__________________ have the same genes in the same order but may carry different alleles, or variants, of the same gene
Homologs
____________ ________________ ______________is a highly regulated program of genetic switches that are turned on in specific body parts at specific times.
Human prenatal development
_____________ __________________ explains why the fate of a gene on one chromosome is not influenced by a gene on a different chromosome.
Independent assortment
___________________ ________________________ explains why the fate of a gene on one chromosome is not influenced by a gene on a different chromosome.
Independent assortment
General sources of human stem cells:
Induced pluripotent, Embryonic, Adult
Two major stages of the cell cycle are ________________(not dividing) ______________(dividing)
Interphase ; mitosis
At which phase of meiosis does the crossing over of homologs occur?
Middle of prophase I
How do mitosis and cytokinesis differ? Mitosis divides __________________________________while cytokinesis divides _______________________________
Mitosis divides the DNA while cytokinesis divides the rest of the cell contents.
_______________is a form of cell death associated with inflammation and damage, rather than orderly, contained destruction.
Necrosis
Which of the following is a diploid cell with which the process of oogenesis begins?
Oogonium
________________ is the transformation of the simple three layers of the embryo into distinct organs.
Organogenesis
Which of the following cellular components are considered part of the cytoplasm?
Pigment molecules
___________ are rapid aging disorders
Progerias
During which phase of the cell cycle does the cell replicate its entire genome?
S phase
Which phase of the cell cycle follows immediately after mitosis and is characterized by the synthesis of cellular components such as proteins, carbohydrates, and lipids?
S phase
In the cell cycle, DNA replication occurs during the ________________________
S phase of interphase
________________________ refers to the process by which sperm are formed
Spermatogenesis
A structure formed from microtubules that separate the chromosomes during mitosis
Spindle
Meiosis:
Used for sexual reproduction Daughter cells are genetically different Produces four daughter cells per cycle
which of the following is an application of conservation genetics?
Using a combination of genetic analysis and reproductive technologies to save the rhinoceros species from extinct
During fertilization, the sperm's ______________ bursts, releasing enzymes that bore through the protective layers surrounding the secondary oocyte.
acrosome
DNA resembles a spiral staircase wherein the rails or backbone, consist of
alternating chemical groups, namely sugars and phosphates
The early cells resulting from the frequent division of the zygote are known as __________
blastomeres
The series of events describing the sequence of activities as a cell prepares for and undergoes division is called the __________________
cell cycle
After DNA replication, each chromosome consists of two copies joined at the ________________
centromere
The placenta is formed from the ____________ ___________of the embryo.
chorionic villi
A day after fertilization, the zygote divides by mitosis, beginning a period of frequent cell division called __________
cleavage
DNA analysis of the mummy of the Egyptian king has revealed that he most likely died from
complications of malaria
what are the basic tissue types:
connective, epithelial, muscle, nervous
The field of _______________ ______________ involves an analysis of genetic diversity combined with reproductive technologies to rebuild animal populations that would otherwise be headed towards extinction
conservative genetics
A sperm first contacts a covering of follicle cells, called the ____________________ ______________, that guards a secondary oocyte.
corona radiata
In the context of an embryo, the time when genetic abnormalities, toxic substances, or viruses can alter a specific structure is known as its ____________ ______________
critical period
Everything but the nucleus, organelles, and the outer boundary in a cell is known as the
cytoplasm
The _____________________is a meshwork of protein rods and tubules that serves as the cell's architecture, positioning organelles and providing overall three-dimensional shapes.
cytoskeleton
__________________helps to maintain the cell's shape, anchors the organelles, and allows the cell and its organelles to move
cytoskeleton
The process that determines which genes are expressed and hence what type of cell wall result is termed
differentiation
The use or expression of different subsets of genes to manufacture proteins drives a specialization of distinctive cell types and is referred to as
differentiation
In humans, somatic cells are _____________ with two copies of each chromosome type.
diploid
Fraternal, or ____________ twins result when two sperm fertilize two oocytes.
dizygotic
Which is the typical inheritance pattern for diseases caused by the "paternal age effect"?:
dominate single- gene mutations
A diploid cell containing eight chromosomes undergoes meiosis. How many chromosomes are present in each cell after meiosis I?
four
The primordial embryo consists of three layers. These are called ______________, _________________, ______________.
ectoderm, endoderm, mesoderm
The female sex cells are called________ or __________
eggs or oocyte
Three general sources of human stem cells:
embryonic stem cells, induced pluripotent their cells, and adult stem cells
In meiosis, the second division is called ______________ ______________, produces four cells from the two cells formed in the first division by splitting the replicated chromosomes.
equational division
In ______________ algorithms search for variance in genes that might explain symptoms of the disease
exome sequencing
A pregnant woman who has just one or two alcoholic drinks a day, or perhaps a large amount at a single crucial time, risks _________ _____________ ________________
fetal alcohol syndrome
During the ____________ _____________ the body proportions approach those of a newborn.
fetal period
To study amyotrophic later sclerosis scientists developed a type of stem cell called an ____________________from fibroblasts that can be reprogrammed to produce a large quantity of ALS ______________ ____________
iPS cell; motor neuron
This figure highlights the phenomenon of _____________ ______________, which helps to generate genetic diversity in meiosis.
independent assortment
During ______________, a cell continues the basic biochemical functions of life, while also replicating its DNA.
interphase
stages of the cell cycle: __________________and _____________
interphase and mitosis
In the context of adult-onset inherited disorders, a fetus that does not receive adequate nutrition has _________________ ______________ ____________, and though born on time, is very small.
intrauterine growth retardation
A process in which the distinctive characteristics of sperm and oocytes are sculpted is known as __________________
maturation
A type of cell division in which the chromosome number is halved is known as _______________
meiosis
Gametes form via a special type of cell division called __________
meiosis
The form of cell division that produces sperm or eggs is called ______________
meiosis
________________ is the field of genomics that reveals and describes much of the invisible living world by sequencing all of the DNA in a particular habitat, in finding out how species interact in a given population.
meta-genomics
know where centromere is on chromosome
middle of the X
Which is the mechanism responsible for the mutations found in sperm due to the "paternal age effect"? :
mistakes in DNA replication
When somatic cells multiply, DNA is divided by a process called ______________, while the division of the rest of the cell is called ________________
mitosis; cytokinesis
The structure formed of microtubules that will pull chromosomes apart during mitosis is called the __________________
mitotic spindle