Biology Chapter 7, 8, 9, 10, 12

A human somatic cell has _______ chromosomes?

46

Linked genes are genes that __________.

are on the same chromosome

2 types of chromosomes

autosomes and sex chromosomes

restriction enzymes

cut DNA at specific sequences

The distribution of cytoplasms to daughter cells is accomplished during

cytokinesis

The chromosomal DNA is duplicated which stage of the cell cycle

interphase

Mitosis

interphase, prophase, metaphase, anaphase, telophase

Nondisjuciton

is the failure of chromsome pairs to separate properly during meiosis.

The information by a DNA molecule is in

the order of the nucleotides in the molecule

mutagenesis

the production of mutations

It's difficult to observe individual chromosomes with a light microscope during interphase because

they have uncoiled to form long, thin strands

Nitrogenous bases

thymine, cytosine, adenine, guanine

In a DNA double helix, adenine pairs with _______- and guanine pairs with _______

thymine.......cytosine

The major contribution of sex to evolution has been

to provide greater genetic variation.

Anaphase 1

Homologous chromosomes separate

Telophase 1

2 daughter cells are formed, each daughter cell contains only one chromosome of the homologous pair.

DNA in a single human cell is about ______ long

2 meters (6.5 feet) long

Dogs have a diploid chromosome number of 78. How many chromosomes do their gametes have?

39

If an intestinal cell in a grasshopper contains 12 chromosomes, then a grasshopper sperm cell contains _____ chromosomes.

6

A human skin cell, in prophase of mitosis, contains 46 chromosomes. How many chromosomes contain in total?

92

Telophase 2

A nuclear membrane forms around the chromosomes in each of the 4 new cells.

A karyotype

A picture of all the chromosomes in a cell arranged in pairs

triple code

A set of three-nucleotide-long words that specify the amino acids for polypeptide chains.

ONLY 2 base pairings can form

A to T G to C

2 kinds of base pairings

A to T , G to C

Surprising new evidence has shown that, in some cases, environmental factors can modify chromosomes in such a way that changes the expression of genes without changing genes themselves or any part of the DNA sequence. These modifications are called epigenetic effects. Epigenetic effects can sometimes even be passed from generation to generation. In what way would this kind of "inheritance" be an exception to Mendel's laws?

According to Mendel's laws, the effects of our environment are not passed on to the next generation.

Telophase

After the chromosome seperates, the cell seals off, Final Phase of Mitosis.

Difference between benign tumor and malignant tumor

Benign tumors do not metastasize; malignant tumors do.

Prophase 1

Chromosomes become visible; nuclear envelope breaks down; crossing-over occurs.

Prophase 2

Chromosomes condense, spindles form in each new cell, and spindle fibers attach to chromosomes.

Metaphase 2

Chromosomes line up at the equator.

Metaphase

Chromosomes line up in the middle

Why is the new DNA strand complementary to the 3" to 5" strands assembled in short segments?

DNA polymerase can assemble DNA only in the 5" to 3" direction

recombinant dna

DNA produced by combining DNA from different sources

Alleles

Different forms of a gene

Meiosis goes wrong

Down syndrome caused by an extra copy of chromosome 21, as a result of nondisjunction.

What is the name for this kind of image?

Karyotype

Which allows sexual reproduction to occur generation after generation?

Meiosis

The ABO blood group in humans is an example of _________________ producing 4 phenotypes.

Multiple alleles

Metaphase 1

Paired homologous chromosomes line up across the center of the cell

Which of the following occurs in meiosis but not mitosis?

Pairing of homologous chromosomea

cell division

Process by which a cell divides into two new daughter cells

asexual reproduction

Process by which a single parent reproduces by itself

Meiosis

Prophase 1, Metaphase 1, Anaphase 1, Telophase 1, Prophase 2, Metaphase 2, Anaphase 2, Telophase 2, Cytokinesis

What phase of the cell cycle does DNA replication occur?

S

Ligase

Short segments of newly synthesized DNA are joined into a continuous strand by _____.

biotechnology

The manipulation of living organisms or their components to produce useful products.

Metastasis

The spread of cancer cells beyond their original site

-ACGT

The sticky end of the DNA restriction fragment shown here will pair with a DNA restriction fragment with the sticky end _____.

Sticky ends

The unpaired nucleotides produced by the action of restriction enzymes are referred to as _____.

unambiguous

a codon for on amino acid does not code for any other amino acid

DNA polymerases

a group of enzymes that bond the new nucleotides together

Meiosis

a type of cell division that results in four daughter cells each with half the number of chromosomes of the parent cell, as in the production of gametes and plant spores.

homologous chromosomes

carry the same genes

Both asexual and sexual reproduction rely on

cell division

Meiosis - me (complicated)

cell division that produces reproductive cells in sexually reproducing organisms

mutation

change in the nucleotide of DNA

Interphase

chromosomes duplicate

Anaphase

chromosomes separate and move to opposite ends of the cell

Human Genome Project

determined the sequence of genes in human DNA

Insulin production

diabetes - caused by insulin deficiency

Cytokinesis

division of the cytoplasm

After DNA replication is completed, _____.

each new DNA double helix consists of one old DNA strand and one new DNA strand

Meiosis only happens in

egg and sperm cells (sexual reproduction)

GgTt pea plants can produce _____ type(s) of gametes, but a ggtt plant can produce _____ type(s) of gametes.

four ... one

The flow of information in a cell proceeds

from DNA to RNA to protein

In general, the frequency with which crossing over occurs between two linked genes depends on _________.

how far apart they are on the chromosome

Telophase

last stage of mitosis

Which term refers to the specific location of a gene on a chromosome?

locus

In humans, the ________ determines the sex of the offspring because ________

male.... the male can contribute an X or Y chromosome.

Plant cells divide by

mitosis followed by cytokinesis by cell plate formation

Prophase

mitotic spindles grow, attach to sister chromatids

redundant

more than one codon for some amino acids

Viruses

not cellular, cannot reproduce on their own, less complex than cells

Mitosis

part of eukaryotic cell division during which the cell nucleus divides

Restriction fragments

pieces of DNA that have been cut into different lengths

4 phases of mitosis

prophase, metaphase, anaphase, telophase

Histones

protein molecules around which DNA is tightly coiled in chromatin

The action of helicase creates

replication forks and replication bubbles

Which of the following is not a function of mitosis in humans?

reproduction of gametes

function of cell division

reproduction, growth and development, healing, sexual reproduction, asexual reproduction

The sex of a human fetus is determined by the....

sex chromosome found in the sperm

nearly universal

shared by all organisms

Anaphase 2

sister chromatids separate

Metaphase 2

sister chromatids separate

Viroids

small circular RNA molecules that infect plants and disrupt their growth

zoonotic disease

spread from animals, caused by viruses, bacteria, 60% of all human diseases originated in other animals

which stage of mitosis is essentially the opposite of prophase in terms of changes within the nucleus?

telophase

Double-helix

two strands of nucleotides wound about each other; structure of DNA

The most common phenotype in a natural population is referred to as the

wild type