EAR-20 Lecture Notes - Lecture 12: Molecular-Weight Size Marker, Genetic Recombination, Mitosis

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lemonwasp425

4 Dec 2020

School

RCC

Department

Early Childhood Education

Course

EAR-20

Professor

Yates

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Keenan Lieu

Spring 2020

Child Growth and Development

Cell Division and Chromosome Duplication

● Each of s began life as a single cell created when a sperm cell, normally containing 23

chromosomes from the father, united with an ovum (egg), normally containing an

additional 23 chromosomes from the mother

● Zygote: fertilized egg cell

● Nearly ever one of the millions of different cells in the newborn, whether specialized for

bone or skin, heart or brain, or in some other way, contains the same genetic blueprint

established in the initial zygote

● Mitosis: process of cell division that takes place In most ells of the human body and

results in a full complement of identical material in the 46 chromosomes in each cell

● During mitosis, genetic material in the nucleus of the cell is reproduced such that

a full complement of DNA becomes available to each new cell

● Before cell division occurs, the chemical bonds linking the nucleotides that

forms the DNA ladder weaken

● Pairs of nucleotides separate as though they are being unzipped from each other

● At the same time additional nucleotides are manufactured in the cell and attach

to the separated nucleotides (each nucleotide can combine with only one other

type)

● The two newly formed strands of DNA are normally rebuilt in exactly their

original sequence

● The two newly formed copies of DNA eventually separate completely so that

one becomes a member of each of the two new daughter cells

● Meiosis: process of cell division that forms the gametes; normally results in 23

chromosomes in each human egg and sperm cell rather than the full complement of 46

● In the first stage, each of the 46 chromosomes begins to replicate in much the

same way as mitosis begins

● Before identical replicas split apart, the cell divides, so that each daughter cell

receives only one chromosome from each of the 23 pairs

● In the second stage, the replicas of the 23 chromosomes completely separate, and

the cell divides once more, each cell again receiving one of the replicas

● Four cells are produced, each with 23 chromosomes

● Crossing over: process during the first stage of meiosis when genetic material is

exchanged between autosomes

● The potential for genetic variability

● The process of genetic recombination makes it virtually impossible for two

individuals to have the same genetic makeup, even siblings, unless the two are

identical

Gene Expression

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Document Summary

Each of s began life as a single cell created when a sperm cell, normally containing 23 chromosomes from the father, united with an ovum (egg), normally containing an additional 23 chromosomes from the mother. Nearly ever one of the millions of different cells in the newborn, whether specialized for bone or skin, heart or brain, or in some other way, contains the same genetic blueprint established in the initial zygote. Mitosis: process of cell division that takes place in most ells of the human body and results in a full complement of identical material in the 46 chromosomes in each cell. During mitosis, genetic material in the nucleus of the cell is reproduced such that a full complement of dna becomes available to each new cell. Before cell division occurs, the chemical bonds linking the nucleotides that forms the dna ladder weaken. Pairs of nucleotides separate as though they are being unzipped from each other.

Related Questions

Chapter 6: How Cells Harvest Chemical Energy

What is the difference between photosynthesis and cellular respiration?

How do cells capture the energy released by cellular respiration?

What are the products of cellular respiration?

What does pyruvate do?

The conversion of CO2 and H2O into organic compounds using energy from light is called what?

If ATP accumulates in a cell, what happens?

A drug is tested in the laboratory and is found to create holes in both mitochondrial membranes. Scientists suspect that the drug will be harmful to human cells because the drug inhibits what?

As a result of glycolysis, there is a net gain of ________ ATP(s).

Which of the following is a result of glycolysis?

The enzymes of the citric acid cycle are located in what?

Chapter 7 Photosynthesis: Using Light to Make Food

What is the name given to organisms that can make their own food and thus sustain themselves without consuming organic molecules derived from other organisms?

What is an example of a photoautotroph?

What is the origin of chloroplasts?

In the chloroplast, sugars are made in a compartment that is filled with a thick fluid called what?

The oxygen released into the air as a product of photosynthesis comes from what?

What is the use and production of CO₂ in both photosynthesis and cellular respiration?

Know the parts of the chloroplast. Which structure in the chloroplast represents the thylakoid membrane?

What molecules are reactants of photosynthesis?

What is the source of energy that provides the boost for electrons during photosynthesis?

Why are most plants green?

Chapter 8: The Cellular Basis of Reproduction and Inheritance

What is called the creation of genetically identical offspring by a single parent, without the participation of sperm and egg?

How do eukaryotic chromosomes differ from prokaryotic chromosomes?

Prior to mitosis, each chromosome of a eukaryotic cell consists of a pair of identical structures are called what?

Eukaryotic cells spend most of their cell cycle in which phase?

What occurs during interphase?

What is the process called by which the cytoplasm of a eukaryotic cell divides to produce two cells?

What is the phase of mitosis during which the mitotic spindle begins to form?

During which phase of mitosis does the nuclear envelope re-form?

What feature of plant cell division distinguishes it from animal cell division?

What features likely accounts for the difference between plant and animal cell cytokinesis?

What must occur for a plant or animal to grow and develop normally?

Chapter 9: Patterns of Inheritance

Most genetic disorders of humans are caused by what type of alleles?

What is the difference between genotypes and phenotypes?

What are the individual features of all organisms?

What does the chromosome theory of inheritance state?

What is the normal complement of sex chromosomes in a human male?

The sex chromosome complement of a normal human female is what?

How many sex chromosomes are in a human gamete?

What is the gene located on a sex chromosome called?

Why are sex-linked conditions more common in men than in women?

Chapter 12: DNA Technology and Genomics

How long has Biotechnology been around?

What do restriction enzymes do?

What are "Sticky ends"?

What is the best definition of a genomic library?

What is a nucleic acid probe?

The only cells that can correctly attach sugars to proteins to form glycoprotein products are what?

How does a vaccine work?

What is the preferred name of the technique used to determine if DNA comes from a particular individual?

The polymerase chain reaction relies upon unusual, heat-resistant ________ that were isolated from bacteria living in hot springs.

Gel electrophoresis sorts DNA molecules on the basis of their what?

If an organismâs diploid chromosome number is 18, how many different possible combinations of homologous chromosomes lining up during meiosis exist for the eggs or sperm produced by that organism?

	A.	512
	B.	9
	C.	18
	D.	128
	E.	36

At the end of metaphase I, _______________ separate.

	A.	sister chromatids
	B.	germ cells
	C.	homologous chromosomes
	D.	haploid chromatids
	E.	centrioles

Mendel observed that dominant traits

	A.	are seen in all of the F1 hybrid pea plants in his experiments.
	B.	are expressed in all plants.
	C.	were absent in the F1 generation of pea plants that he used in his experiments.
	D.	were the only traits seen in the F2 generation of pea plants in his experiments.
	E.	are only expressed in hybrids.

Cytokinesis in plant cells differs from cytokinesis in animal cells because

	A.	there is no difference.
	B.	in plant cells, the cell plate must also divide into two parts.
	C.	the contractile protein, actin, is important only in plant cells.
	D.	plant cells have a rigid cell wall.
	E.	a contractile ring forms only in plant cells.

Sickle cell anemia is an example of what type of inheritance?

	A.	complete dominance
	B.	incomplete dominance
	C.	codominance
	D.	multiple alleles
	E.	recessive dominance

Which of the following statements is true:

	A.	The dominant allele is masked in homozygous dominant individuals.
	B.	With recessive genetic disorders, if both parents are carriers, the offspring will all be affected.
	C.	In carriers, the recessive allele causes an intermediate phenotype.
	D.	In recessive genetic disorders, the mother and/or father of an affected individual must also be affected.
	E.	With dominant genetic disorders, the mother and/or father of an affected individual must also be affected.

Skin cancers typically develop in the

	A.	upper layers of the epidermis.
	B.	lower layers of the dermis.
	C.	subcutaneous layer.
	D.	lower layers of the epidermis.
	E.	upper layers of the dermis.

Duchenne muscular dystrophy (MD) is inherited from an X-linked recessive allele. What is the probability that a son with Duchenne MD inherited this disease from his biological father?

	A.	1/2
	B.	0
	C.	1/16
	D.	1/4
	E.	1/8

The genetic makeup of a particular trait in an individual is its

	A.	genotype.
	B.	heterozygosity.
	C.	phenotype.
	D.	filial.
	E.	dominance.

What structure holds the sister chromatids to the spindle fibers?

	A.	chromatin
	B.	kinetochore
	C.	MPF
	D.	centromere
	E.	cyclin

If you view a cell in which the genetic material is beginning to be visible as separate bodies, and the nucleus has disappeared from view, you may surmise that the cells is in

	A.	telophase.
	B.	anaphase.
	C.	interphase.
	D.	metaphase.
	E.	prophase.

Gregor Mendel was successful in his analysis of the genetics of pea plants because

	A.	he examined and analyzed both the F1 and F2 generations.
	B.	he studied the parental plants to determine their differences.
	C.	he decided to only look at his results in an objective manner.
	D.	he studied a trait that had a strange inheritance pattern.
	E.	pea plants have genetics different from other organisms.

Tall corn plants (T) are dominant to dwarf plants (tt). Solid green leaves (G) are dominant to leaves with a white tip (gg). A cross between two corn plants yielded the following phenotypes: 51 tall plants with a white tip on their leaves; 43 dwarf plants with solid leaves; 48 dwarf plants with white tips on their leaves; 45 tall plants with solid leaves. What are the genotypes of the parents that produced these plants?

	A.	None of the above
	B.	TtGg x Ttgg
	C.	ttGG x TTgg
	D.	TtGg x TtGg
	E.	TtGg x ttgg

In humans, a gene that has been identified as causing a type of skin cancer is the

	A.	superwoman echidna.
	B.	mutant superman.
	C.	sonic hedgehog.
	D.	mutant mole rat.
	E.	superhero aardvark.

The segregation principle states that in sexually reproducing diploid organisms the two copies of each gene

	A.	segregate from each other during meiosis.
	B.	must always be the same allele.
	C.	separate from each other during mitosis.
	D.	will both wind up in either the sperm or egg.
	E.	move together as a unit during meiosis.

In what phases is the genetic material in the cell correctly referred to as chromatids?

	A.	metaphase and telophase
	B.	anaphase and metaphase
	C.	interphase and telophase
	D.	interphase and prophase
	E.	metaphase and prophase

Consider two traits for an organism, determined by two genes, each of which is governed by at least two alleles. In the case of a dihybrid individual, the gametes formed will be of either the parental type or the recombinant type. Recombinant type gametes are formed because of

	A.	the principle of dihybrids.
	B.	multiple alleles.
	C.	heterozygosity.
	D.	incomplete dominance.
	E.	independent assortment.

An allele is

	A.	an alternate form of a gene.
	B.	always recessive.
	C.	the main factor determining a trait.
	D.	always one of a pair.
	E.	the dominant form of a gene.

After the DNA is replicated, and it condenses in prophase, two identical rods of DNA are seen. These are

	A.	spindle fibers.
	B.	kinetochores.
	C.	chromatids.
	D.	chromatin.
	E.	centromeres.

Special cells found in the gonads that give rise to gametes upon division are called

	A.	egg cells.
	B.	somatic cells.
	C.	germ cells.
	D.	stem cells.
	E.	basal cells.