Human bio reproductive test

What is a stem cell

A stem cell can differentiate into different kinds of cells and tissues. Can also make copies of itself creating more stem cells

What are the 4 types of stem cells

totipotent, pluripotent, multipotent, unipotent

What does the totipotent stem cell do

Can form any kind of cell in the body and only found in cygote

What does a pluripotent stem cell do

Can form any kind of body cell and found in blastocysts

What does a multipotent stem cell do

Can only divide into certain types of tissue

What does a unipotent stem cell do

Unspecilalised cells that can only become one type of cell

What is the first step for induced pluripotency

Somatic cell isolation and culture

What is the second step in induced pluripotency

Introduction of reprogramming

What is the third step for induced pluripotency

Reporgramming

What is the fourth step for induced pluripotency

Culture and selection

What is the fifth step for induced pluripotency

Identification and characterisation

What is the cell cycle

The events that take place from one cell division to the next are called the cell cycle

Describe the Gi phase of the cell cycle

The cell producers new proteins, grows and carries out it's normal tasks for the body

Describe the S phase of the cell cycle

The DNA molecules in the cell nucleous from exact copies of themselves

Describe the G2 phase of the cell cycle

This relatively short phase involves preparation for cell division

Describe the M phase of the cell cycle

The cell division divides into two daughter cells, after division the cells may continue the cycle and re enter the Gi phase

mitosis

A type of cell division where 1 parent cell divides once to produce 2 identical daughter cells

What is chromatin

A complex of DNA and proteins found inside the nucleous of eukaryotic cells

What is the primary function of chromatin

Primary function to package very long DNA molecules into more compact denses structures that can fit within the tiny cell nucleus

Why is mitosis important

Creates new body cells that are needed for growth, repair and maintinence

Meiosis

A type of cell division where 1 parent cell divides twice to produce 4 non identical daughter cells

Why is meiosis important

Meiosis allows for the continuity of a species because it means that organism can produce offspring with new gene combinations

What are gametes

Sperm and ova that are produced in the ovaries and testes, are the result of a special type of cell division and meiosis

What is haploid number

Daughter cell with half the number of chromosomes that were present in the original cell

What is the diploid

The number of chromosomes in body cells

What are homologous chromosomes

The chromosomes in diploid cells actually exist in pairs that are identical in shape and carry genetic information that influence the same characteristics

What is genetic variation

A term used to describe the differences between the gametes of individuals of the same species

What is independent assortment

What the genes for different traits sperate into gametes independently of each other, meaning the inheritance of one trait doesn't affect the inheritance of another

What is crossing over

When two paired chromosomes exchange segments of their DNA during the formation of sperm and egg cells, creating new combinations of genetic material

What is fertilization

The joining of a male reproductive cell and a female reproductive cell to form a new single cell, which then develops into a new organism

What is non disjunction

Sometimes one or more of the chromosome pairs may fail to separate when the cell divides in the second meritoic divisions one or more of the chromatids may fail to separate

What is trisomy

A condition in which an individual inherits an extra copy of a chromosome

What is monosomy

Where individuals are missing a chromosome

what is cancer

It is the uncontrolled division of cells that causes the growth of a mass known as a tumor

How are tumors classified

maligant - can spread to other parts of the body

Berign - do not spread to other parts of the body

What are some causes of cancer

Carcinogens are environmental factors known to cause cancer, uv radiation, x-rays, runising radiation, viruses

How can cancer be prevented

Education, legislation, avoid smoking, using sunscreen, personal protective equipment

What is a gene

The fundamental unit of heredity in living organisms

How many genes are in each cell

between 19,000 and 20,000

What 3 things make up a nucleotide

A nitrogen base, a pentose sugar, a phosphate group

What does a triplet contain the information for

A specific amino acid or a stop signal

What are coding and non coding genes

Coding genes are the segments of DNA that contain the instructions for building proteins and non coding genes are regions of DNA that do not directly code for proteins

Describe the process of DNA replication

If order for a cell to divide it must duplicate it's DNA

What is the function of the penis

The penis is the organ that transfers sperm from the male to the female

What is the function of the erectile tissue

Made of spongy tissue and fills with blood during an erection

What is the function of the urethra

Carries sperm outside of the body

What is the function of the foreskin

A sheath of skin that covers the head of the penis

What is the function of testes

The key role of the testes is to produce sperm and hormones

What is the function of the scrotum

The scrotum is a shin covered pouch that hold the testes

What is the function of semin ferrous tubules

Lined with cells which produce sperm

What is the function of the empidymis

Store sperm while they mature

What is the function of interstital cells

Secrete testosterone

What is the function of vas deferens

Carries the sperm away from the testes towards the urethra

What is semen

Sperm transported in liquid called semen

What are seminal vesicles

Secrete thick sugary fluid which provides nutrient for sperm

What is the function of the prostate gland

Secretes thin milky alkaline fluid which neutralises the acidic pH of the vagina

What is the function of the bulbo urethral gland

Secretes a clear mucus that acts as lubricant

What is the function of the ovaries

Contain undeveloped eggs present from birth, make hormones which regulate the mesntural cycle, one of the ovaries release a mature ovum as part of the ovarian cycle

What are the fallopian tubes

Two tubes that connect the ovaries to the uterus

What is the function of the fallopian tubes

Lined with hair like cells called cilia to help move the ovum from the ovary to the uterus

What is the fimbriae

Finger liked projections at the beginning of the fallopian tubes that guide the egg from the ovary into the tube

What is the uterus

A muscular with a soft mucous lining called the endometrium

What is the function of the uterus

The uterus has a role in protecting and nourishing the developing foetus

What is the endometrium

A soft mucus lining

What is the function of the endometrium

The endometrium is shed if an ovum is not fertilised by a sperm

What is the cervix

A ring muscle which dictates to open during labour

What is the vagina

A muscular tube which corrects the cervix to outside the body

What is the hymen

A fold of tissue which covers the opening to the vagina

What is the vulva

Made up of external genital organs of the female

What is the labia major

Two fleshy folds that contain oil secreting glands

What is the labia minora

Beneath the labia major and surround the space to which the urethra and vagina open

What is the clitoris

At the upper end of the labia minora is the elators which contains erectile tissue which fills with blood when stimulated

Where does spermatogenesis occur

Occurs inside the seminferous tubules inside the testes

What is the onset of spermatogenesis

During puberty, the cells lining the seminiferous tubules divide by mitosis

Number of gametes produced by spermatogenesis

four

Where does oogenesis occur

Inside the ovaries

Number of gametes produced by oogenesis

one

What is an oogonium

A diploid germ cell found in the ovaries of female animals and in certain algae and fungi

Define the term primary sex characteristics

Characteristics of sex organs

Define the term secondary sex characteristics

Any physical characteristic that are different between the sexes but are not directly included in reproduction

Define the term hormone

A hormone is a chemical substances, produced by a gland, and carried by the blood, which alters the activity of one or more specific target organs

What do sex hormones do

Sex hormones play a role in the development of primary and secondary sex characteristics

What do FSH and LH do in males

promote the production of testosterone in the testes

What is testosterone

Main male reproductive hormone

What does testosterone do

Stimulates the production of sperm in the testes and helps in development of secondary sex characteristics in males

What does FSH and LH do in females

Effect the ovaries and stimulate the release of oestrogen and progesterone

What does oestrogen do

Travels in blood and promotes breast development and other sex characteristics

What do the endocrine glands do

Release hormones directly into the blood stream

Explain what the ovarian cycle is

A series of events that take place in the ovaries causing the development of follicles and corpus luteum

What long does the ovarian cycle take

28 days

What is the first step of the ovarian cycle

Surrounding the primary oocyte is a single layer of cells called the primary follicle

What is the second step of the ovarian cycle

At puberty, follicle stimulating and lutenising hormone are secreted

What is the third step of the ovarian cycle

In response to FSH and LH, the cells of the primary follicle, enlarge, divide and secrete fluid into the space around the oocyte

What is the fourth step of the ovarian cycle?

More fluid accumulates inside the follicle and the follicle moves to the surface of the ovary

What is the fifth step of the ovarian cycle

At day 14 there is a spike in LH and FSH and this causes ovulation to occur

What is the sixth step of the ovarian cycle

The ruptured follicle forms a blood clot

What is the seventh step of the ovarian cycle

These cells enlarge and form the corpus luteum

What is step 8A of the ovarian cycle

If fertilization does not take place after 8-10 days it will degrade and become the corpus albicom

What is step 8B of the ovarian cycle

If fertilization takes place the corpus luteum remains for 3 months