Mendal - reproudction test

what is Asexual reproduction

a type of reproduction in which one parent produces offspring that are all genetically identical to the parent

what is genetic material

information that is stored in DNA and passed onto the next generation by asexual or sexual reproduction

what is offspring

new organisms that are produced by asexual or sexual reporoduction

what are some of the pro’s for asexual reproduction

pros are only needs one parent, doesn’t take much energy, and it is fast, con’s are it has the same DNA as it’s parent so it can’t adapt to new environments well from traits it might have gotten from the other parent, they are all genetically the same so if a virus comes around it has a chance of wiping out an entire population

what is binary fission

a form of asexual reproduction used by bacteria (parent cell splits into two parts)

what is parthenogenesis

asexual reproduction where an egg develops WITHOUT fertilisation

what is fragmentation

asexual reproduction that occurs when a new organism grows from a fragment of another

what are all the types of Asexual reproduction

binary fission, parthengenesis, and fragmentation

what is sexual reproduction

type of reproduction in which two parents produce offspring that are genetically different to the parents; the fusion of gametes from two parents

what are some of the pros and cons for sexual reproduction

pros are more genetically diverse, can adpat to new environments, more immune to illness, cons are needs two parents, takes more energy, slower process

what is fertilisation

the process where two gamets (sex cells) fuse to produce a signle cell

what are all the types of fertilisation

external, internal

what is external fertilisation

when the egg and sperm meet outside the bodies of the parents - in water

pros and cons of external fertilisation

pros are more eggs are laid, low parental energy, the mother doesnt have to carry the children so can reproduce more quickly again, cons are lower chance of survival and the eggs might not meet the sperm, egg and sperm wastage, less protected out in the open

pros and cons for internal fertilisation

pros are higher success rate, is more protected in the mother stomach, better parental care. cons takes more energy from the parents, fewer offspring porduced, takes more time

what are r-strategist

organisms living in unstable environmets that breed rapidly

k- strategists

are organisms living in stable environments who breed carefully

what organisms are likely to recieve more parental care and why

k-strategists as there are fewer born in a more controlled enviroment which means the parents are able to take care of them better.

which organism is more likley to be independent

r- strategist as they don’t receive much parental care and must learn how to survive in more unstable environments on their own

how do plants reproduce asexually

producing genetically identical clones from a single parent without gamete fusion,

how does cross pollination work

the pollen from one plant attaches to the stigma and digs a pollen tube down to the ovary, and then transfers the pollen to the stigma. Pollen lands on stigma- Grows a pollen tube down to ovary- Sperm travels to fertilise egg

what is pollination

transfer of pollen from anther to stigma

what are gamets

sex cells (egg in girls, sperm in guys)

what are clones

an organism that is genetically identical to another

what is mitosis

the process of cell division that results in gentetically identical daughter cells- creating the same cell for growth or repair

what is cytokinesis

the splitting of a replicating cell into two cells

what are somatic cells

the body cells exept gamets

what is interphase

a phase of a cell life where normal functioning occurs

what are the stages of the cell cycle

interphase prophase, metaphase Anaphase, telophase cytokines,

why does the the rate of mitosis need to be controlled

becuase cells do not last forever and need to be programed into a cell’s DNA, when something goes wrong this can cause mutagens that can lead to cancer

what is a diploid

it contains two sets of complete chromosomes

why is cell division important

so they can grow or repair damage

what is interphase

normal life of the cell

what is prophase

chromosomes apear, nucleus membrane disappears, spindle forms,

what is metaphase

chromosomes line up in a sigle line across the center with spindle fibres attached to the centromere

what is Anaphase

each pair of chromatids seperate at the centromere, each chromatid moves to the side,

what is telophase

necear membrane re-forms

what is cytokinesis stage

cytoplasm divides (two daughter cells are produced)

what is a haploid

it contains one complete set of chromosomes in each cell eg gamets

what is meiosis

the process that results in the formation of gametes with half of the genetic material of the parent cell

what happends in fertilisation interms of the gametes

Gametes contain 23 chromosomes, made up of 22 autosomes (chromosome thats not a sex cell) and 1 sex chromosome (X or Y), which combine during fertilisation to restore the full number of 46 chromosomes. due to this everytime the order of the chromosomes in the egg or sperm will always be different which how siblings look different

what is the process of Meiosis

phrophase I, Metaphase I, Anaphase I, Telophase I and cytokinesis , Phrophase II, Metaphase II, Anaphase II, Telophase II and cytokinesis

Prophase I

Chromosomes condense and become visible. Homologous chromosomes pair up (synapsis) to form tetrads. Crossing over occurs where DNA is exchanged between chromosomes. Nuclear membrane breaks down and spindle fibres form.

Metaphase I

Tetrads line up along the middle (equator) of the cell. Spindle fibres attach to homologous chromosomes. The orientation is random (independent assortment).

Anaphase I

Homologous chromosomes are pulled apart to opposite poles of the cell. Sister chromatids remain joined together.

Telophase I & Cytokinesis

Chromosomes reach opposite ends. Nuclear membranes may reform. The cell divides into two haploid cells (each has half the number of chromosomes).

what happends in prophase II

two daughter cells will be in the new cell the spindle fibres wil start to get ready

what happends in Metaphase II

Chromosomes line up at the equator. Spindle fibres attach to the centromeres of sister chromatids.

what happends at Anaphase II

Sister chromatids are separated and pulled to opposite poles of the cell.

what happends at telophase II and cytokinesis

Chromosomes reach the poles, Nuclear membranes reform. Cells divide, resulting in four genetically different haploid cells.

what is fertilisation in plants

fusion of gametes (happens after pollination)