Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

biology yr 12 > chapter 2 😎 > Flashcards

chapter 2 😎 Flashcards

1
Q

allele

A

One of various versions of the same gene (at the same locus) distinguished by small differences in the DNA sequence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

apoptosis

A

A programmed series of events that leads to cell death (as a result of the dismantling of the internal contents of the cell by various enzymes, including caspases)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

asexual reproduction

A

The process by which a single parent produces offspring and that does not involve fusion of gametes; a process that usually results in identical offspring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

autosome

A

A chromosome that is not a sex chromosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

binary fission

A

The division of a cell into two cells without mitosis; a prokaryotic cell undergoes binary fission to form two identical daughter cells; a form of asexual reproduction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

bivalent

A

A structure (visible in a cell during prophase I of meiosis) made up of two homologous chromosomes joined together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

cell cycle

A

An ordered sequence of events in the life of a cell from when it was formed from a parent cell until its own division

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

cell division

A

The splitting of a cell into two new functioning cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

cell plate

A

The structure produced by dividing plant cells in the place where the new cell wall is forming

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

centriole

A

A minute rod-shaped organelle present in many resting cells, just outside the nuclear membrane that helps make the spindle fibres for cell division; a centrosome contains two centrioles; it is usually absent in plants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

centromere

A

The waist-like constriction in a chromosome where the spindle fibres attach; it enables the movement of chromosomes during cell division

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

centrosome

A

An organelle containing a pair of centrioles; it duplicates during cell division, while the DNA is duplicating, and the two centrosomes then separate to opposite poles of the dividing cell; it produces the spindle during cell mitosis and meiosis, and one of the centrosomes goes into each daughter cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

chromatid

A

Daughter strand of a duplicated chromosome that is joined to another chromatid by a centromere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

chromatin

A

An organised, loosely coiled complex of DNA and its proteins that is found in eukaryotic non-dividing cells; it is more compact than the DNA of prokaryotes; chromatin supercoils to become the chromosomes observable during eukaryotic cell division

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

chromosome

A

A structure composed of DNA and protein that contains linear arrays of genes carrying genetic information; prokaryotes generally have one circular chromosome, whereas eukaryotes have a number of linear chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

cleavage

A

The division of the cytoplasm in an animal cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

cleavage furrow

A

A shallow, ring-like depression that forms on the surface of an animal cell undergoing cytokinesis as contractile microfilaments pull the cell membrane inward; it defines where the cytoplasm will be divided to make two cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

crossing over

A

The exchange of genetic material between maternal and paternal homologous chromosomes (of non-sister chromatids) that occurs during the first step of meoisis (prophase I)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

cytokinesis

A

The division of the cytoplasm immediately after mitosis, meiosis I or meiosis II to create two separate daughter cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

differentiation

A

The process during development whereby newly formed cells become more specialised as they mature; an example of cell differentiation is the development of root tip cells of plants into phloem, xylem and root hairs; during the process of differentiation, cells gain specialised structures and functions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Diploid (2n)

A

Describes a cell or organism that has a genome that contains two copies of each chromosome(one from each parent); the diploid number of chromosomes is represented by 2n

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

DNA (deoxyribonucleic acid)

A

The information-containing molecule present in all living things that contains the instructions, written in a chemical code, for the production of proteins by the cell; the information it contains is sufficient for the making and maintaining of the organism; in addition, DNA is the genetic material that passes this information on to the next generation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Eukaryotic cell

A

A complex cell containing membrane-bound organelles,including a nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Fertilisation

A

The fusion of haploid male and female gametes during sexual reproduction to produce a diploid zygote; the random union of gametes is known as random fertilisation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
gametes
A male or female reproductive cell; one of each type combine at fertilisation; in humans, the gametes are ova and sperm cells; in flowering plants, pollen grains contain male gametes and ovules contain female gametes
26
gene
A unit of heredity that transmits information from one generation to the next; a segment of DNA that codes for a polypeptide
27
genetic
Refers to the mechanisms and patterns of inheritance; relating to the transmission of coded chemical instructions from one generation to the next
28
genome
All of the genetic material contained in an organism or a cell; it includes the chromosomes within the nucleus and the DNA in mitochondria and chloroplasts
29
Germline cell
A specialised sex cell that gives rise to gametes; early in an embyro’s development, its germline cells specialise into male or female germ cells
30
Haploid (n)
Describes a cell or organism that has a genome that contains one copy of each chromosome; the haploid number of chromosomes is represented by n
31
Heredity
The study of inheritance; the genetic transmission of characteristics from one generation to another
32
Heterosome
One of the non-identical chromosomes that pairs up at meiosis (e.g. the X and Y chromosomes in male humans)
33
histone
A protein around which DNA winds in eukaryotic cells to form a nucleosome
34
Homologous chromosomes
A pair of chromosomes of the same size and shape and that has the same genes at the same locations
35
Interphase
The stage between nuclear divisions that involves metabolic activity, growth, and duplication of chromosomes
36
Karyotype
A display of the number and appearance of the chromosomes of an organism or cell as observed at metaphase
37
Locus (plural loci)
The position a gene occupies on a chromosome
38
Maternal chromosome
The chromosome in a pair of chromosomes that came from the mother
39
meiosis
A type of cellular division in sexually reproducing organisms that involves two rounds of cell division, but only one round of DNA replication; during meiosis, the chromosome number of a cell is halved so that the daughter cells are haploid; meiosis is the basis of gamete formation in some plants and animals and of spore formation in other plants
40
mitosis
A type of nuclear division in somatic cells that maintains the parental diploid number of chromosomes in the daughter cells; it is the basis of bodily growth and of asexual reproduction in many eukaryotic species
41
Nitrogenous base
A structural component of the nucleotides that make up DNA or RNA
42
Nucleoid
The region within a prokaryotic cell that contains the genetic material
43
Nucleolus
A structure found within the nucleus of a non-dividing cell; a site in which ribosomes are made from protein and RNA subunits
44
Nucleotide
The basic building block of nucleic acids (DNA and RNA); nucleotides are linked together by phosphodiester bonds; each nucleotide is made up of a five-carbon sugar, a phosphate group and a nitrogenous base
45
Nucleus
The dense organelle of a eukaryotic cell that contains genetic material in the form of chromosomes and is enclosed by a nuclear membrane; in its resting phase, the genetic material takes the form of loosely coiled chromatin; the chromatin supercoils and condenses to form chromosomes before cell division
46
organelle
A specialised part of a cell that has its own specific function; a ‘little organ’
47
Paternal chromosome
The chromosome in a pair of chromosomes that came from the father
48
Plasmid
A small circular piece of DNA, found in bacteria, that is able to replicate independently of the cell’s chromosomes; engineered plasmids may carry antibiotic-resistance markers
49
prokaryote
A single-celled organism that lacks membrane-bound organelles such as a nucleus
50
sex chromosome
A chromosome that determines the sex of an organism and affects sexual traits
51
Sexual reproduction
A form of reproduction in which offspring are produced from two parents by the fusion of male and female gametes
52
somatic cell
A body cell that is not a germ cell
53
synapsis
Synapsis The pairing of homologous chromosomes during prophase I of meiosis
54
synapsis
The pairing of homologous chromosomes during prophase I of meiosis
55
trait
An inheritable characteristic; phenotype
56
zygote
The first cell of a new individual; it is formed by fusion of a male and a female gamete (fertilisation) during sexual reproduction
57
why do Chromatin Condenses to Form Chromosomes
Chromatin (the loose, thread-like form of DNA) condenses to form tightly coiled chromosomes to make the genetic material more manageable. Condensed chromosomes are easier to move and separate without breaking during cell division, ensuring each new cell will get a full set of DNA.
58
why Nuclear Membrane Disintegrates and Nucleolus Disappears
The nuclear membrane and nucleolus (which makes ribosomes) break down to give spindle fibers access to the chromosomes. The nuclear membrane acts as a barrier, so disintegration allows chromosomes to interact with the spindle fibers and enables their distribution to daughter cells.
59
why Mitotic Spindle Begins to Form
The mitotic spindle is a structure made of microtubules that helps to organize and sort chromosomes during division. It forms to guide chromosomes to the correct locations within the cell, ensuring each daughter cell receives the right set of chromosomes. This step is crucial for accurate cell division and preventing genetic abnormalities.
60
why Centrosomes (Each Containing Two Centrioles) Move Toward Opposite Poles of the Cell
Centrosomes act as the main microtubule-organizing centers. Moving to opposite poles allows the mitotic spindle to form between them, creating the structure that will guide and pull chromosomes apart. Positioning the centrosomes on opposite sides ensures that the spindle fibers can equally divide chromosomes to both new cells.
61
genetic code
instructions that determines the sequence of amino acids in a protein

biology yr 12 (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions