CELLS

Learning Objectives that cells form tissues, and tissues form organs to name some important tissues in humans to explain the organisation of tissues using a model that there are different types of cell, adapted for different functions to use secondary sources of information

What are living organisms made from? Basically, all living things are made up of cells… A group of CELLS makes up a TISSUE A group of TISSUES makes up an ORGAN A group of ORGANS makes up a SYSTEM A group of SYSTEMS make up an ORGANISM

Muscle cells Muscle tissue Organ System Organism What are living organisms made from?

Human Body Tissues Epithelial tissues serve as membranes lining organs and helping to keep the body's organs separate, in place and protected Connective tissues adds support and structure to the body Muscle tissues specialised tissue that can contract Nerve tissues generate and conduct electrical signals in the body

Organ Systems Circulatory system Oxygen is carried by blood, blood is pumped by the heart.

Organ Systems Nervous System The nervous system is responsible for sending, receiving, and processing nerve impulses throughout the body. Ex. brain, spinal cord

Organ Systems Respiratory System In the respiratory system, the lungs are the organs that take in the oxygen muscles need.

Organ Systems Digestive System In the digestive system, the stomach and the intestines are the organs that get sugars from the food you eat. Blood carries these sugars to the muscles.

Organ Systems Reproductive system Major Organs: Female: ovaries, oviducts, uterus, vagina and mammary glands. Male: testes, seminal vesicles and penis.

Singular cell organisms functions like respiration, feeding, moving, expelling wastes, reproduction, etc. are carried out by the single cell Ex. Amoeba, paramecium MxtKUhttp:// MxtKU csdY&feature=fvwhttp:// csdY&feature=fvw –p p p p

Specialised Cells Some cells have very specialised functions These cells have special features, or adaptations, in order to carry out their special function

Root Hair Cell These cells are found near to the tip of the roots of plants Most water and nutrients enter plants through them It has a large surface area to speed up the absorption of water and mineral salts from the soil.

Research Poster You are going to be making a A3 poster with information about a specialised cell You need to use google to find images and websites to find out information on these cells. If you use a website, you must make a note of the address. Copy it and put it in a reference section in the corner of your poster!

Poster criteria –Have a clear title and subtitles –Explain specialised cell function –Identify where the cell is found –Identify special features that help the cell perform its specialised function –Have clear pictures –not have lots of text copied from a website –Have a reference section where you can put your used websites in

Specialised cells Choose one or more from: –Sperm cell –Egg cell –Palisade cell –Ciliated cell –Nerve cell –Red blood cell –White blood cell

Specialised cells Sperm cell –Designed to carry genetic information to an egg –They have a tail which they use for swimming –They have a pointed head to penetrate the egg –The head of the sperm contains special chemicals that help it penetrate the egg –They have little cytoplasm so they can swim faster

Specialised cells Egg cell –Designed to be fertilised –An ovum is large and bulky because no active movement is needed - it just sits and waits for the sperm to find it –It contains yolk (in the cytoplasm) which provides a large food store needed for the developing young organism once it's fertilised –Once the sperm fertilizes the egg, the egg swells pushing away other sperm, so it can only be fertilized once

Specialised cells Palisade cell –Designed for photosynthesis –They are tall and narrow so that lots of cells can fit close together –They are found on the top side of a leaf - ideal for good absorption of carbon dioxide and light - both are needed for photosynthesis –They're packed with chloroplasts, which contain the green pigment chlorophyll, which is needed for photosynthesis

Specialised cells Ciliated cell –To remove mucus, to remove bacteria, move liquid over the cell's surface. –In humans, ciliated cells are found, for example, in the lining of the windpipe, where they sweep mucus and dirt out of the lungs, and in the oviducts, where they move the ovum from the ovary to the uterus –They have tiny hairs that beat to move things over the cell surface

Specialised cells Nerve cell –To carry messages throughout the body –They are very long so they can carry messages to different parts of the body –They have many branches at the end so they can connect with many other nerve cells

Specialised cells Red blood cells –To carry oxygen from the lungs to the parts of the body where it is needed –They are shaped to give them a large surface area so they can absorb oxygen more easily –The cytoplasm contains a chemical called ‘haemoglobin’ which carries oxygen –Have no nucleus so there is more room for oxygen to be carried in the cell and hence around the body –Their shape makes them flexible which means cells can squeeze through the thinnest of capillaries

Specialised cells White blood cell –To help the immune system –Some are flexible, so they can engulf foreign objects, viruses, bacteria and fungal infections –Some can remember dangerous infections, and therefore protect against them better next time