-
What is the largest object in the cell, and is whereDNA, the main genetic material is stored?
nucleus
-
What two membranes are the nucleus surrounded by?
nuclear membrane or nuclear envelope
-
What are large openings through the envelope thatallow cytoplasmic material (like proteins) to enter and nuclear products (likeribosomes) to exit the nucleus?
Nuclear pores
-
What is inside the nucleus?
nucleolus, chromatin, and enzymes to make RNA and DNA
-
What is a dark region within the nucleus; it is an area of intense ribosome synthesis and assembly?
nucleolus
-
______ is what chromosomes are made of.
Chromatin
-
Sections of the DNA molecule can be copied tomake RNA – these sections are called?
genes
-
Two copies of the same DNA molecule are called?
chromatids or sister chromatids
-
The two ends of the chromosome/DNA molecule are called?
telomeres
-
After replication, the cell has twice as muchDNA as it did before replication, but it still has only 46 chromosomes. Why?
This is because both copies of a chromosome areconnected by a common centromere.
-
Each telomere acts as a “cap” on the end to prevent chromosomes from sticking together – the telomere does not contain genes.
-
Most complex organisms are built of ___ ____, which means each cell actually has 2 sets of chromosomes.
diploid cells
-
Each chromosome in a set is __________ with one of the chromosomes in the other set - two chromosomes that are ________ are the same size and shape, and both contain the same genes at thesame place on the DNA molecule
homologous
-
Of the23 pairs of homologous chromosomes in humans, 22 pairs are ______ and do not determine sex.
autosomes
-
The ____ ____ is the period from the time a new cell is formed until it finishes dividing to form 2 new cells (20minutes for some bacteria, years for some human cells).
cell cycle
-
For most cells in the body, the cycle is divided into _______(the period between nuclear divisions) and _____(one type of nuclear division; the cell itself usually divides while thenucleus is dividing).
Interphase; mitosis
-
Most of the cell cycle is spent in ________ –this is when most cell metabolism occurs.
Interphase
-
What is Interphase made up of?
G1, S Phase, and G2
-
What is the period of growth following cell division?
G1
-
What is it called when the DNA is replicated in preparation for cell division?
S Phase
-
What is the second period of growth prior to next mitosis?
G2
-
During each of these stages these is at least one ________– a period when the decision is made to either continue progressing towards cell division, or to stop for a while and carry out neededDNA or cell repairs or processes.
checkpoint
-
What is accomplished when a cleavage furrow (contractilering of cytoskeleton actin and myosin) gradually "pinches thecell in half"?
Cell or cytoplasmic division (cytokinesis)
-
What can be either mitosis or meiosis?
Nuclear division (karyokinesis)
-
_____is how most cells in your body divide and multiply.
mitosis
-
______is how sperm and egg cells are formed.
meiosis
-
What type of nuclear division produces 2 daughter nuclei, identical to each other and to the orginal parent nucleus?
mitosis
-
Which type of nuclear division produces 4 genetically different nuclei (or cells) with only 23 chromosomes each, or half the normal chromosome number?
meiosis
-
What type of cell has only one set of chromosomes? And what are the examples in the human body?
haploid; sperm and egg cells
-
What are the steps of nuclear division?
- Prophase
- Metaphase
- Anaphase
- Telophase
-
What is the most common type of nuclear division?
mitosis
-
Which step of nuclear division is this? Chromosomes condense and become visible, nuclear membranes and nucleolus disappear, microtubules assemble to form spindle apparatus
Prophase
-
Which step of nuclear division is this? Chromosomes line up across cell equator on metaphase plate, chromosomes can be counted.
Metaphase
-
Which step of nuclear division is this? Chromatids are separated and one chromatid is pulled to each pole (opposite sidesof cell) – pulling is done by microtubules of spindle.
Anaphase
-
Which step of nuclear division is this? Nuclei reform, chromosomes and spindledisappear, cell divides.
Telophase
-
What are the subunits of nucleic acids?
Nucleotides
-
What are the nitrogenous bases found in DNA?
- Adenine
- Thymine
- Guanine
- Cytosine
-
What are the nitrogenous bases found in RNA?
- Adenine
- Uracil
- Guanine
- Cytosine
-
Guanine always base pairs with?
Cytosine
-
Adenine always base pairs with?
Thymine or Uracil
-
The DNA molecule is actually a ____-_____ ______, with the two strand sheld together by hydrogen bonds between the complementary bases of the two strands.
double-stranded polymer
-
Each gene carries a sequence of bases that will be copied to make one ____.
RNA
-
An ____ molecule is a single-strandednucleic acid.
RNA
-
DNA synthesis is called ____ ______, and only occurs during S phase.
DNA replication
-
New nucleotides will pair up with the exposed bases, and an enzyme (____ _____) will covalently bond the nucleotides into a new DNA strand.
DNA polymerase
-
DNA polymerase not only builds new DNA, it also ______-______ as it builds, and should a mispairing occur (A with G), it will removethe incorrect base and add the right one.
proof-reads
-
DNA polymerase can also repair damaged DNA during interphase, and is called the "____-_____ _____ _______."
error-proof repair system
-
What special enzyme is required to replicate the telomere?
telomerase
|
|