2. Cell Division Flashcards
Fill the blank
A ____ is a segment of DNA in which we find genetic information that allows the production of a particular molecule or that determines a specific character.
gene
What name is given to the basic functional and structural unit of all living organisms?
cell
Name the four phases of the cell cycle.
G1
S (synthesis)
G2
M (mitosis)
Explain the difference between a haploid and a diploid cell.
Haploid cells have only one full set of chromosomes. In humans, the only haploid cells are germ cells (sperm and eggs) produced by meiosis.
Diploid cells have two distinct sets of chromosomes. In humans, all somatic cells are diploid and are produced by mitosis.
Name the two types of (eukaryotic) cell division.
- mitosis
- meiosis
Mitosis produces (somatic) cells that are identical to the parent, while meiosis produces germ cells with only half of the parental genetic material.
Name four broad differences between mitosis and meiosis.
1.Mitosis involves a single division, while meiosis involves two.
2.Mitosis produces two identical diploid cells, while meiosis
produces up to four haploid cells that are not identical.
3.Mitosis is used to form somatic cells, while meiosis produces germ cells (gametes).
4.Crossing over occurs in meiosis, but does not happen in mitosis.
somatic cell are cell that are not germ cell
Mitosis is broadly similar, but not identical, to meiosis I. Name three differences between the two processes.
1.Mitosis involves the separation of sister chromatids, while meiosis I involves the separation of homologous chromosomes.
2.Mitosis produces diploid cells, while the products of meiosis I are haploid.
3.Crossing over occurs in prophase of meiosis I, but does not occur at all during mitosis.
Which process of genetic recombination occurs during prophase I of meiosis?
Crossing over, or the trading of DNA segments between homologous chromosomes, occurs when these chromosomes are paired together in prophase I.
Define
sister chromatid
1.Sister chromatids are genetically identical, as they result from the replication of a single chromosome.
2.Sister chromatids separate during meiosis II and mitosis.
Fill in the blank
The human genome has around ____
25000 genes
Define:
Diploid Cells
Diploid cells have 2 sets of chromosomes - one from the mother and one from the father. Diploid cells are formed during mitosis.
True or False
The number of chromosomes can vary in healthy individuals of the same species with no genetic abnormalities.
False!
Describe
Mitosis: Prophase
1.Phase 1 of Mitosis
- Chromosomes are formed (DNA strands arecondensed)
- Nuclear membrane disappears
Fill the blanks:
23rd pair is ___ for females and ___ for males
XX for females
XY for males
Fill the blank
____ ____ increases the capacity of a species to adapt and decreases the risk of extinction.
Genetic diversity
True or False:
Genes contain the necessary information to manufacture protein.
True
Genes contain all the necessary information to manufacture proteins such enzymes and hormones and so on.
In turn, each protein has a specific job to do, such as digesting nutrient, repairing wounds, giving the eyes their color, etc…
Identify:
Molecule that controls all cell activity.
DNA: deoxyribonucleic acid
Identify
Contains all organelles and many other dissolved substances.
Cytosol
True of false
DNA contains all the genetic information of an individual.
True
Fill the blank
_____ is the form in which chromosomes are entangled and folded up on themselves. This form is found outside the phases of nuclear division
Chromatin
Fill in the blanks:
____is the variety of different genetic combinations amoung members of the same ____
1)Genetic diversity
2)species
Fill in the blank:
Every ____ can exist in different variations and forms.
Gene
Fill the blank:
At the beginning of cell division, the DNA strands coil and condense to form ____
Chromosomes
What cellular events characterize (mitosis) metaphase?
The chromosomes line up along the center of the cell, a region called the metaphase plate.
Identify
Process in which cells multiply to ensure growth and to repair tissue
Mitosis
During which stage of meiosis do daughter cells become haploid?
During Meiosis I, a pair of chromosome separates. This leaves two daughter cells, each with a single chromosome from each pair and its replicated copy.
What cellular events characterize (mitosis) anaphase?
Sister chromatids are cleaved apart
What cellular events characterize (mitosis) telophase?
1.The cell elongates.
2.Each daughter cell forms a new nuclear membrane.
3.The chromosomes start to become less condensed.
True or False
Sister chromatoid are exact copies of each other.
True.
True or False
For each inherited trait, only one gene is involved.
False!
Sometimes a single gene is responsible for an inherited trait, and in other cases several genes are linked to the same trait.
Fill the blank
A ____ is the condensed version of DNA that forms only during cell division.
Chromosome
Fill the blank:
(In the diploid cells), humans have ____
23 pairs of chromosomes
Fill the blanks
During _____ _____, chromosomes take the form of a pair of Xs where each of the two branches of an X is called a ____\ _____
cell division
sister chromatid
Define
Meiosis
The process in which female and male gametes areproduced in order for reproduction to take place(production of gametes for reproduction)
another name for meiosis is gametogenesis!