Cholesterol

LEARNING OUTCOMES Describe the effects of cholesterol on the body

Describe the effects of cholesterol on the body

The good, the bad, and the even better Saturated Mono-unsaturated Poly-unsaturated the bad The good The even better

Restoring the balance Saturated fats (“bad fats”) increase cholesterol levels. Mono-unsaturated fats and polyunsaturates may help reduce cholesterol and restore the balance between LDLs and HDLs.

The problem with cholesterol Sometimes cholesterol in the blood sticks to the inside of artery walls. As it builds up it forms a plaque, this restricts the flow of blood. Sometimes, the cholesterol can break away and block the artery completely .

Sometimes cholesterol in the blood sticks to the inside of artery walls.

As it builds up it forms a plaque, this restricts the flow of blood.

Sometimes, the cholesterol can break away and block the artery completely .

Statins Statins are a group of chemicals which prevent all of the cholesterol being absorbed in to the blood stream This lowers peoples overall cholesterol – which can reduce health problems

Statins are a group of chemicals which prevent all of the cholesterol being absorbed in to the blood stream

This lowers peoples overall cholesterol – which can reduce health problems

The Big Picture

Mitosis v Meiosis

LEARNING OUTCOMES Compare and contrast meiosis and mitosis Describe adaptations of a sperm cell

Compare and contrast meiosis and mitosis

Describe adaptations of a sperm cell

The Big Picture

Egg Haploid 23 chromosomes Sperm Haploid 23 chromosomes Zygote (fertilised egg) Diploid 46 chromosomes Cell in ovary Diploid 46 chromosomes Cell in testes Diploid 46 chromosomes Fertilisation Meiosis Meiosis Mitosis

Cell division – the differences MITOSIS MEIOSIS Diploid cells / 2n Haploid cells / n (1) Produces identical cells Produces different cells Involves 1 cell division 2 cell divisions Makes 2 daughter cells Makes 4 daughter cells

Sperm adaptations Acrosome - contains enzymes to digest the egg cell membrane Tail – many mitochondria in cells to release energy. WHY

Acrosome - contains enzymes to digest the egg cell membrane

Tail – many mitochondria in cells to release energy.

WHY

ENZYMES DIGESTS EGG MEMBRANE / PENETRATE / GET INSIDE THE EGG RESPIRATION

MITOSIS – DIPLOID CELLS (46 CHROMOSOMES) MEIOSIS – HAPLOID CELLS (23 CHROMOSOMES) MITOSIS – IDENTICAL CELLS MEIOSIS – DIFFERENT CELLS MITOSIS – 1 CELL DIVISIONS MEIOSIS – 2 CELL DIVISIONS MITOSIS 2 DAUGHTER CELLS MEIOSIS 4 DAUGHTER CELLS

The Big Picture

Growth spurts

LEARNING OUTCOMES Explain why gestation periods differ in different animals State that different parts of a foetus and baby grow at different rates Describe the main phases of human growth

Explain why gestation periods differ in different animals

State that different parts of a foetus and baby grow at different rates

Describe the main phases of human growth

Human growth Put the stages of human growth in the correct order, starting with the earliest: Adulthood (maturity) Childhood Infancy Old age Adolescence (puberty) What stage of growth are you in?

Put the stages of human growth in the correct order, starting with the earliest:

Adulthood (maturity)

Childhood

Infancy

Old age

Adolescence (puberty)

What stage of growth are you in?

The Big Picture

Plant cells and growth

LEARNING OUTCOMES Compare and contrast an animal and plant cell State how animals and plants grow differently Explain animal and plant growth in terms of cell growth

Compare and contrast an animal and plant cell

State how animals and plants grow differently

Explain animal and plant growth in terms of cell growth

Chloroplasts Cell Wall Vacuole Cell Membrane Nucleus Cytoplasm

Plant and animal cells Name three structures found in a plant cell but not in an animal cell Name three structures found in both a plant cell and an animal cell

Name three structures found in a plant cell but not in an animal cell

Name three structures found in both a plant cell and an animal cell

Growth

Growth Plant Most growth is due to cells elongating (growing longer) not dividing Cell division only normally occurs at the tips of shoots and roots Many cells never lose the ability to differentiate Animal Growth is due to cells dividing Cell division occurs all over the body Most animal cells lose the ability to differentiate very early on

Plant

Most growth is due to cells elongating (growing longer) not dividing

Cell division only normally occurs at the tips of shoots and roots

Many cells never lose the ability to differentiate

Animal

Growth is due to cells dividing

Cell division occurs all over the body

Most animal cells lose the ability to differentiate very early on

LEARNING OUTCOMES Compare and contrast an animal and plant cell State how animals and plants grow differently Explain animal and plant growth in terms of cell growth

Compare and contrast an animal and plant cell

State how animals and plants grow differently

Explain animal and plant growth in terms of cell growth