Module 5 Flashcards
Sexual reproduction
A reproductive process that involves two parents that combine their genetic material to produce a new organism, which differs from both parents
Asexual reproduction
reproduction involving 1 parent with offspring that are genetically identical to parents
Internal fertilisation
fertilization of an egg by sperm that occurs inside the body of a female
Mitosis
cell division in which the nucleus divides into nuclei containing the same number of chromosomes
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.
Fertilisation
Process in sexual reproduction in which male and female reproductive cells join to form a new cell
Budding
- a type of asexual reproduction in which a new organism develops from an outgrowth or bud due to cell division at one particular site. The bulb like projection coming out from the yeast cell is called a bud.
Spores
- tiny unicellular reproductive cells
- produced in the sporangia and are dispersed into the environment
- enables a species to expand the area they colonise due to their lightness
Binary fission
(“division in half”) is a kind of asexual reproduction. It is the most common form of reproduction in prokaryotes such as bacteria. It occurs in some single-celled Eukaryotes like the Amoeba and the Paramoecium.
Nucleotide pairing
A with T & G with C – This forms the double helix
Transcription
(genetics) the organic process whereby the DNA sequence in a gene is copied into mRNA
Translation
(genetics) the process whereby genetic information coded in messenger RNA directs the formation of a specific protein at a ribosome in the cytoplasm
mRNA
messenger RNA; type of RNA that carries instructions from DNA in the nucleus to the ribosome
Fertilisation in plants
If a pollen grain lands on the stigma of a plant, a pollen tube will grow out of the pollen grain, down through the style to the ovary and into the ovule. A nucleus from the male gamete then moves down the pollen tube and will fuse with the nucleus of the female gamete, which is fertilisation. A fertilised female gamete forms a seeds and the ovary develops into a fruit around the seed.
Hormones
Chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another
Angiosperms
flowering plants
Haploid
(genetics) an organism or cell having only one complete set of chromosomes
Diploid
(genetics) an organism or cell having two sets of chromosomes or twice the haploid numb
Testosterone
Male sex hormone
Oestrogen
Female sex hormone which stimulates the lining of the womb to build up in preparation for a pregnancy.
Progesterone
hormone produced by the corpus luteum in the ovary and the placenta of pregnant women
Vegetative propagation
A form of asexual reproduction in which plants produce genetically identical offshoots (clones) of themselves, which then develop into independent plants.
LH (luteinizing hormone)
Produced by Anterior lobe of Pituitary Gland. Targets ovaries and testes to stimulate estrogen secretion and egg maturation; stimulates sperm production.
FSH (follicle stimulating hormone)
A form of asexual reproduction in which plants produce genetically identical offshoots (clones) of themselves, which then develop into independent plants.
Germination
the process whereby seeds or spores sprout and begin to grow
DNA replication
DNA unzips into two parts and splits with the cell. In it’s new home each side of the DNA strand attack to matching nucleotides to create 2 exact copies
Flashcards
https://quizlet.com/au/321046137/hsc-biology-flash-cards/
advantages of asexual reproduction
- quicker
- less energy required
- no need to find mate (less energy)
- offspring have a competitive advantage
how does variation arise? [asexual and sexual]
asexual = mutations in DNA sexual = meiosis, genetic recombination, fertilisation
why does reproduction occur?
reproduction is important for the survival of all living things as it ensures the continuity of the species, without a mechanism of reproduction, species would become extinct and life would come to an end
disadvantages of asexual reproduction
- no adaptations as they lack variation and as a result can be vulnerable
- rapid reproduction leads to high competition for resources and overcrowding
- unprotected
advantages of sexual reproduction
- diverse offspring with genetic variation with the ability to adapt
- protected offspring
- less risky
- genetic diversity
disadvantages of sexual reproduction
- slower process and therefore can make animal vulnerable (to predator)
- need to find and/or compete for a mate (and therefore more energy needed)
- more energy needed to reproduce
runners
a horizontal stem that grows along the surface of the soil and produces an offspring off a node on the stolon of the stem
rhizomes
a horizontal stem that grows underground and produces an offspring off a node on the stolon of the stem
suckers
roots that are produced from the main root and give rise to offspring
Alleles
alternative forms of a gene
Asexual reproduction
a type of reproduction by which offspring arise from a single organism, and inherit the genes of that parent only
Carrier
a heterozygous individual not expressing a recessive trait but capable of passing it on to its offspring
Centromere
The replicated arms of the chromosome are held together by this structure.
Cervix
elongate inferior end of the uterus where it connects to the vagina
Chromosome
structures within the nucleus made of DNA that contain all the genetic information of an organism
Chromatids
one of the two halves of a duplicated chromosome
Cloning
a cell, cell product, or organism that is genetically identical to the unit or individual from which it was derived.
Corpus luteum
transformed follicle after ovulation that secretes progesterone
Diploid
Having two sets of chromosomes or double the haploid number of chromosomes. with One member of each chromosome pair comes from the ovum and one from the sperm.
DNA (deoxyribonucleic acid)
The chemical compound that makes up genes within chromosomes and is the basic material of heredity. Two chains of nucleotides twist around each other to form a double helix.
Dominant allele
an allele that is always expressed when present, regardless of whether the organism is homozygous or heterozygous for that gene.
Endometrium
inner lining of the uterus, part of which builds up during the secretory phase of the menstrual cycle and then sheds with menses
Epididymis
(plural = epididymides) coiled tubular structure in which sperm start to mature and are stored until ejaculation
External fertilisation-
sperm fertilises egg outside female body.
Fragmentation
a form of asexual reproduction in which an organism is split into fragments. Each of these fragments develop into matured, fully grown individuals that are identical to their parents.
Gamete
a haploid (n) sex cell in plants and animals (egg or sperm)
Gene
a discrete unit of hereditary information that usually specifies a protein; a region of DNA (locus) located on a chromosome that specifies a trait (characteristic).
Gene pool
all the genes in a population.
Genetics
The study of genes and inheritance patterns
Genotype
the genetic make-up of an individual. Eg Bb
Gonadotropin-releasing hormone (GnRH)
hormone released by the hypothalamus that regulates the production of follicle-stimulating hormone and luteinizing hormone from the pituitary gland
Haploid
one set of chromosomes per cell (n) found in the sex cells (23 in humans)
Heterozygous
possessing a pair of unlike alleles for a particular gene.
Homozygous
possessing a pair of identical alleles for a particular gene.
Homologous chromosomes
chromosomes that are similar in shape and form and the genes they consist of. One set comes from the father and the other from the mother.
Inheritance
The transmission of genetic information from a parent to a child
Meiosis
The special cell division which only takes place in the sex cells of females and males, resulting in egg and sperm cells that contain 23 chromosomes (the haploid number). ‘Daughter’ cells not identical to parent cells.
Menstrual cycle
approximately 28-day cycle of changes in the uterus consisting of a menses phase, a proliferative phase, and a secretory phase
Mitosis
The process of cell division in body cells. Mitosis results in ‘daughter’ cells which are genetically identical to the parent cells.
Mutation
A permanent, heritable change in the base sequence in a gene or a chromosome;
Oocyte
cell that results from the division of the oogonium and undergoes meiosis I at the LH surge and meiosis II at fertilization to become a haploid ovum
Oogenesis
process by which oogonia divide by mitosis to primary oocytes, which undergo meiosis to produce the secondary oocyte and, upon fertilization, the ovum
Ovarian cycle
approximately 28-day cycle of changes in the ovary consisting of a follicular phase and a luteal phase
Ovaries
female gonads that produce oocytes and sex steroid hormones (notably estrogen and progesterone)
Ovulation
release of a secondary oocyte and associated granulosa cells from an ovary
Ovum
haploid female gamete resulting from completion of meiosis II at fertilization
Parthenogenesis
reproduction from an ovum without fertilization, especially as a normal process in some invertebrates and lower plants
Penis
male organ of copulation
Phenotype
the physical or chemical expression of an organism’s genes. Eg Brown eyes
Polar body
smaller cell produced during the process of meiosis in oogenesis
Prostate gland
doughnut-shaped gland at the base of the bladder surrounding the urethra and contributing fluid to semen during ejaculationscrotum external pouch of skin and muscle that houses the testes
Recessive allele
an allele that is only expressed when the organism is homozygous for that allele and not expressed when heterozygous (when paired with a dominant allele).
Semen
ejaculatory fluid composed of sperm and secretions from the seminal vesicles, prostate, and bulbourethral glands
Seminal vesicle
gland that produces seminal fluid, which contributes to semen
Selective Breeding
The intentional breeding of organisms with desirable trait in an attempt to produce offspring with similar desirable characteristics or with improved traits.
Seminiferous tubules
tube structures within the testes where spermatogenesis occurs
Sexual reproduction-
the production of new living organisms by combining genetic information from two individuals of different types (sexes).
SNPS-
Single nucleotide polymorphisms, frequently called SNPs (pronounced “snips”), are the most common type of genetic variation among people. Each SNP represents a difference in a single nucleotide.
Sperm
-(also, spermatozoon) male gamete
Spores
- a reproductive cell capable of developing into a new individual without fusion with another reproductive cell. Spores are produced by bacteria, fungi, algae, and plants.
Testes
singular = testis) male gonads
Uterus
muscular hollow organ in which a fertilized egg develops into a fetus
Vagina
tunnel-like organ that provides access to the uterus for the insertion of semen and from the uterus
Zygote
- diploid (2n) cell resulting from the union of two gametes in sexual reproduction
Which go together
A T G C
AT (apple tree)
GC (car garage)
4 enzymes in DNA replication
primase
helicase
ligase
DNA polymerase
Nitrogenous bases
Either Adenine, Thymine, Guanine or Cytosine
Helicase function
Unzipping the DNA helix
Primase function
Synthesising an RNA primer
DNA polymerase
adding bases to the new DNA chain; proodreading the chain for mistakes
Removing RNA primers, replacing gaos between OKazaki fragments with correct nucleotides, repairing mismacthed bases
Ligase
final binding of nicks in DNA during synthesis and repair
what base changes between dna and rna
NA doesn’t contain thymine bases, replacing them with uracil bases (U), which pair to adenine
Phenotype
An individual’s phenotype is a combination of environment and genetic expression
Where is DNA found in prokaryotes?
DNA in prokaryotes is found in free floating chromosomes within the cytoplasm, not bound by any proteins. Prokaryotes also have small, extra-chromosomal DNA segments called Plasmids.
Where is DNA found in Eukaryotes?
DNA in eukaryotes is found in chromosomes within the cell nucleus. DNA is wound tightly around proteins called histones; DNA then forms supercoils which in turn pack together to form a chromosome.
