Bio HSC Mod 1

Pro’s of Sexual Reproduction

• High genetic variability

• facilitates adaptation

• “speeds up” evolution

Con’s of sexual Reproduction

• Energy costly

• mateship is resource and time consuming

• usually sacrifices the fitness of one sex

pro’s of asexual reproduction

• energy efficient

• no need for mateship

• fitness of parent is not affected

Cons of Asexual reproduction

• low genetic variability

• adaptation only occurs via mutation hence adaptation to environment is difficult

• “retards” evolution

Internal fertilisation

• occurs inside the female reproductive tract

• few gametes released

• high chance of fertilisation

• high parental investment

• high offspring survival rate

• typically occurs in terrestrial environments and sometimes aquatic

External fertilisation

• occurs in the environment generally water

• many gametes released

• low chance of fertilisation

• low to no parental investment

• lower offspring survival rate

• usually occurs in aquatic envirnoments

Reproductive processes of animals

sexually

• internally

• externally

Reproductive processes of plants

asexually

• runners

• bulbs

• cuttings

sexually

• pollen

Reproductive processes of fungi

asexually

• spores

• budding

sexually

• spores

Reproductive processes of bacteria

asexually

• binary fission

Reproductive processes of protists

asexually

• binary fission

role and function of oestrogen

• made in placenta

• stimulates ovulation

• aids blood flow to offspring

• aids organ development of offspring

• stimulates progesterone

role and function of Progesterone

• first mad by ovaries then placenta

• stimulates thickening of uterus lining

• aids placenta function and relaxes uterus

• helps mothers immune system tolerate infant

role and function of Relaxin

• loosens uterine muscles

• prepares the females body for birth

role and function of oxytocin

• stimulates production of milk

• trigger uterine contractions

role and function of luteinising hormone

• promotes final maturation of the ovarian follicle, oculation and development of the corpus luteum

role and function of follicle stimulating hormone

• stimulates the maturation of follicles in the ovaries of females

role and function of HCG

• produced by the developing placenta

• signlas the body to keep producing progesterone

• thickens uterine lining and tells the body to stop menstruating

definition of natural breeding as manipulation of reproduction

placing a male and a female in an enclosed environment and waiting

definition of artificial insemination as manipulation of reproduction

taking sperm from a male and inserting it directly into the females reproductive tract

definition of artificial pollination as manipulation of reproduction

Taking pollen from one flower and inserting it into another flower

definition of cloning as manipulation of reproduction

creating a genetically identical copy of an organism

Positives of manipulating reproduction in agriculture

• increased production

• improved quality

• increase resistance to pests and disease

• economical

negatives of manipulating reproduction in agriculture

• reduced biodiversity

• variation in a species decreases

• population is more likely to suffer from environmental changes

characteristics of Mitosis

• no genetic recombination > no variation

• 2 diploid cells produced

• 46 chromosomes in daughter cells

• occurs across the body

• growth and repair

• 4 stages + interphase

characteristics of meiosis

• genetic recombination produces four new unique haploid cells

• 23 chromosomes in daughter cells

• occurs in reproductive organs

• essential for reproduction and increases of genetic variability

• 8 stages plus interphase

Interphase

• cell growth

• contents excluding chromosomes are replicated

• synthesis

• each of the chromosomes are duplicated

• proof reading

• cell checks the chromosomes for errors

Mitosis > _____

Cytokinesis > _____

Mitosis > nucleus divides

Cytokinesis > Cytoplasm divides

Cytokinesis

name the stages in mitosis

Prophase

• chromosomes condense and become visible as two identical joined strands

• nuclear membrane breaks down

metaphase

• chromosomes line up along the centre of the cell

anaphase

• chromatids are separated from their counterpart and pulled by spindle fibres to opposite sides of the cell

Telophase

• new nuclear membrane forms around the two sets of chromosomes

cytokinesis

• cytoplasm divides

• two new diploid daughter cells are produced

Meiosis

affect of cell replication on the continuity of a species

• ensures the transmission of genetic information

• supports the growth and repair of organisms

• introduces genetic variation necessary for evolution

Features of Prokaryotes

• no nucleus or membrane bound organelles

• circular DNA shape

• DNA located in cytoplasm

• small relative amount of DNA

• e.g. bacteria and archaea

• generally unicellular

features of eukaryotes

• contains a nucleus and membrane bound organelles

• linear DNA shape

• DNA located in nucleus

• large relative amount of DNA

• e.g. animals and plants

• generally multicellular

DNA > mRNA > tRNA > Protein

DNA (stores genetic code) > mRNA (copies genetic code) > tRNA (turns genetic code into protein chain) > Protein

Characteristics of DNA

• Structure

  • deoxyribose sugar

  • phosphate group

  • Bases - GCAT