Module 1 : Heredity Flashcards
What is the bulb vegetative reproduction, give an example ?
underground storage organ that consists of a short stem surrounded by fleshy leaves - lateral buds eg Onions
What is runners vegetative reproduction give an example ?
side branches that grow close to the ground and develop new plantlets on them eg strawberries
How do animals reproduce ?
Both asexual and sexual. Asexual like budding (coral) or regeneration (flatworms). Sexual can be seen in external or internal fertilisation
What are two advantages and disadvantages of Sexual reproduction
A : high genetic diversity + facilitates adaptation + less prone to environmental changes
D : Energy costly + requires two parents
Name two advantages and disadvantages of Asexual reproduction
A : energy efficient + requires 1 parent + no courtship required
D : less genetic diversity + more prone to environmental changes
List advantages and disadvantages of Internal and external fertilisation ?
A I : fertilisation more likely to occur + offspring more likely to survive
D I : higher amount of energy to occur + less offspring produced
A E : Little energy required + large amount of offspring produced
D E : many gametes go unfertilised + offspring not protected by parents
Explain how fungi reproduce asexually ?
By the 1 of the processes known as spores. Fungi produce spores that disperse from the parent organism by either floating on the wind or hitching a ride on an animal
Explain how fungi reproduce sexually ?
Specialised Haploid Hyphae fuse together to form a diploid cell (2n) —- This genetically unique diploid cell then undergoes meiosis to produce new haploid (n) spores.
Explain binary fission ?
- cell elongates - builds more cell wall
- bacteria genome replicates and remains attached to the membrane.
- Duplicated DNA beings to replicate, moving towards the poles as the cell elongates more
- cleavage furrows begins to form and cell wall forms in cleavage furrows
- two identical are now produced.
Explain budding ?
form of asexual reproduction in which the new organism arises as an outgrowth or bud from the parent
commonly seen in fungi and protists
List the male reproductive parts of a flower and describe the function of each part.
The male gametophyte is the pollen grain, held on the anther at the top of stamen. It is used for to be picked up by bees or wind and transferred onto the female pistil to undergo fertilisation.
label the female reproductive parts of a flower and describe the function of each part.
The pistil includes the stigma, style and ovary. The stigma is used for the pollen grains to germinate, the pollen grains go down the style to reach the ovary in which the egg is held.
Distinguish between pollination and fertilisation in plant reproduction.
Pollination refers to when pollen from the anther is transferred on the female pistil of a angiosperm. Fertilisation however refers to the fuse of haploid gametes to fertilise into a diploid zygote.
Identify two ways in which the reproductive structures differ between wind-pollinated and insect-pollinated plants.
- Wind pollinated plants need to have pollen grains much lighter in weight due to the necessity of being carried by wind.
- Insect pollinate plants need to have more sticky pollen grains in stick onto insects such a bee’s and then carried to another plant.
Describe two pollination mechanisms in plants and explain how they ensure the continuity of the species
- Cross pollination occurs when pollen is delivered from the stamen of one flower to the stigma of a flower on another plant of the same species. This mechanism ensures greater variation in the offspring. Plants additionally use self-pollination is the transfer of pollen from the anther is deposited on the stigma of the same flower.
Identify Mitosis and meiosis
Mitosis - process where a single cell divides into TWO identical daughter cells
Meiosis - process where a single cell divides twice to produce FOUR cells containing half the original amount of genetic information
What are the five hormones
- **FSH :** **Follicle Stimulating Hormone →** from follicles – increases oestrogen and stimulates follicle growth - causes egg to mature and ovaries to secrete oestrogen
- **Oestrogen →** thickens urine lining **→** inhibits the secretion of FSH and LH → stimulates the secretion of LH → development of the female secondary sexual characteristic
- **LH : Luteinising Hormone -** bring on ovulation
- **Progesterone →** Maintain of uterus lining, Inhibits FSH, LH
- HCG - pregnancy hormone - maintains corpus letup
What causes the egg to mature
LH
Causes ovaries to secrete oestrogen
FSH - Follicle Stimulating Hormone
What thickens the lining
Oestrogen
What does a hormone graph look like with the four hormones
Follicular phase - all steady - progesterone and oestrogen starts to increase
Ovulation - 3 peak - LH on top with FSH at the bottom but progesterone steadies out
Luteal Phase - progesterone top and oestrogen bottom peace
Gymnosperm reproduction
pollination occurs by wind - starts as a haploid stage - seperate from female and male cones. small pollen grains from male cones transport to female.
Identify rhimzones and give an example
Ginger : underground stem to new shoots and roots - along the bottom of the growth and stems along the top.
Identify suckers and give an example
new shoots from roots ef wattle tree
Identify tubers and give an example
Potato’s : underground stems with buds
What is a nucleotide
A phosphate group + 5 carbon sugar + nitrogen base
name 3 ways in which variation exists within meiosis
- CROSSING OVER RANDOM ASSORTMENT : alleles are transferred exchanging genetic material - in prophase
- RANDOM/ INDEPENDENT ASSORTMENT OF CHROMASE : : the random orientation of pairs of homologous chromosomes in meiosis I
- RANDOM FUSION OF GAMETES FROM DIFFERENT PARENTS:
random fertilisation from parents.
Name the 5 steps to Mitosis
i propsed men arent tall
- interphase
- Prophase
- Metaphase (middle)
- Anaphase (away)
- Telophase (Two cells)
Whats the importance of mitosis
provides new cells for growth and for replacement of worn-out cells
Name the steps to Meiosis
- interphase I
- Prophase I
- Metaphase I (middle)
- Anaphase I (away)
- Telophase I (Two haploid cells)
- Prophase II
7, Metaphase II - Anaphase II
- Telophase II
Identify the steps to DNA REPLICATION and name the proteins utilised
- HELICASE causes the DNA to unwind
- RNA PRIMER provides a starting point for DNA synthesis for free nucleotide base pairs with complementary bases on both chains.
- leading and lagging
- lagging strands called okazaki fragments which are joined together by LIGASE - DNA POLYMERASE corrects a base parining error
- LIGASE seals the strands.
whats the effect of cell replication for continuity of species
DNA replication = reproduction of cells with important info on life and allows cells to be replicated for growth and for replacement of worn-out cells
What are all the alleles in a population referred to as
gene pool
what is an antigen
any foreign substance that causes an immune response
What is a co-dominance
both alleles are independently and equally expressed eg brown and white cow = white and brown spotted cow
what is incomplete dominance
heterozygous genotype that results in a BLEND of alleles in the phenotype eg white and red flower = pink flower
whats the difference between DNA replication and Protein synthesis
protein synthesis is the production of a functional protein molecule based on the information in the genes whereas DNA replication is the production of an exact replica of an existing DNA molecule.
outline the process of transcription in Polypeptide synthesis
- Transcription occurs in nucleus
- DNA unwinds and acts as a template for the formation of mRNA
- once made mRNA leaves the nucleus and moves to the ribosome in the cytoplasm.
diploid s haploid
Diploid = COMPLETE Haploid = half
what are the protein structures
Primary : order of amino acids
Secondary : folding into repeat patterns
Tertiary : three dimensional arrangement of a polypeptide
Quaternary structure : multi polypeptide chains
describe the structure of-proteins
3D structures made of chains of amino acids
distinguish between protein and polypeptide
peptide - are short chains of 2-50 amino acids
polypeptide - are linear molecules made up of multiple polypeptides
proteins - area functional unit made up of one or more polypeptide
- have very defined structure determine by sequence and folding of amino acids
what are amino acids
simple organic compounds that are the building blocks of proteins
what is transcription
the process by which a complementary copy known as mRNA, of a gene is made in the nucleus.
what is translation
Ribosomes bind to mRNA in the cytoplasm and move along the molecule in a 5’ – 3’ direction until it reaches a start codon (AUG)
Anticodons on tRNA molecules align opposite appropriate codons according to complementary base pairing (e.g. AUG = UAC)
Each tRNA molecule carries a specific amino acid (according to the genetic code)
Ribosomes catalyse the formation of peptide bonds between adjacent amino acids (via condensation reactions)
The ribosome moves along the mRNA molecule synthesising a polypeptide chain until it reaches a stop codon
At this point translation ceases and the polypeptide chain is released
what is the difference between gene and allele
gene - a sequence of bases at a particular locus in a DNA molecule eg coding for eye colour
allele - is an alternative form of gene eg gene codes for eye colour has blue, brown and green allele
what is mRNA
single strand of nucleic acid, (A,U, G,C)
what is tRNA
small RNA molecule that transfers specific amino acids to the ribosomes during formation of polypeptides
what is codon
set of three nitrogen bases in mRNA
what is anticodon
complementary set of three nitrogen bases in tRNA
what is the importance of mRNA in transciption
DNA cannot leave the nucluos. as a result a messanger must be sent from the nucleus to ribsomoes in the cyolplams of the cell where protein synthesis occurs
what is the importance of tRNA in translation
The role of transfer RNA (tRNA) in translation is to bring specific amino acids to the ribosome, which are then matched up to the mRNA blueprints.
During translation, the type of amino acid that is added to the growing polypeptide chain depends on what
Both the mRNA codon and the tRNA anticodon
outline the process of translation in Polypeptide synthesis
- in the ribsome
- the ribsome reads the nuclotide seuqence in three(codon) with each having a corressponding anti-condon on tRNA
- the adjacent amino acids bind to form a polypeptode chain, representing the genetic information of dna
what is the difference between structures in DNA and RNA
RNA is single-stranded while DNA is double-stranded. RNA contains uracil while DNA contains thymine. RNA has the sugar ribose while DNA has the sugar deoxyribose.
what are 4 ways that may impact the way genes are expressed
- adding a methly group
- histones
- chromatin
4, non-coding RNA
what are the five ways in which formation of new genotypes occur
- co-dominace
- muliltple alleles
- incomplete domiance
- sex-linked
- autosmal
what is dna sequencing
to determine the exact sequence of based to determine patterns of inheritance
what is dna profilling
DNA fingerprinting or profiling comprises any DNA-based techniques that identifies the DNA from a certain individual or group of individuals within a community of organisms.
what are the three cellular processes that must occur inorder for the organisms to surivive
DNA REPLICATION
MITOSIS
MEIOSIS
