unit 4 bio

nervous system

main organs: brain, spinal cord, nerves

function: transmits signals between the brain and the rest of the body. And controls the whole body.

circulatory system

main organs: heart, arteries, veins, the blood

function: transports oxygen and all nutrients in the blood to all body parts

respiratory system

main organs: lungs, nasal cavity (nose), trachea, the diaphragm

function: transfers oxygen into the blood and removes carbon dioxide from the blood to release into the air

muscular system

includes all types of muscles

function: allow body movement

immune system

main organs: lymphatic vessels that transport the lymph, the lymph nodes, the spleen, the thymus, the bone marrow, etc.

function: protect the body from infections and diseases

digestive system

main organs: the mouth, the esophagus, the stomach, the small intestine, the big intestine, the liver, the gallbladder, and the pancreas

function: break down food , eliminates waste

how long does the digestive process take

24-33 hours

excretory/urinary system

main organs: two kidneys, two ureters, a bladder, and a urethra

function: filter blood from toxins, eliminate excess salts and water from the body, regulates the level of water and salt in the body

Integumentary system

Main organs: the skin, hair, and nails

Function: acts as a barrier against infections and injury, protecting the body, it regulates body temperature(sweat), protects against ultraviolent radiation

endocrine system

Main organs: multiple glands in the body

Function: produces all the hormones that coordinate the organ’s interactions

reproductive system

Main organs:

male: penis, testes, and sperm ducts

female: uterus, the vagina, the ovaries and oviduct

Function: male and female produce gamete cells that will create an embryo

female: responsible for growing the embryo “foetus develops” and give birth to the baby.

fertilisation - female gamete cell

egg (ovum), 23 chromosomes

fertilisation - male gamete cell

sperm cell, 23 chromosomes

what is a skeleton

a skeleton is made up of bones, cartilage, ligaments, and joints

our skeleton helps us to do many things, including:

helping us move, giving the body structure and shape, holding us upright (supporting the body), protecting our organs, producing blood cells, storing minerals

Joints:

where 2 or more bones meet

ligament:

a band of fibrous connective tissue that holds bones together

cartilage:

a connective tissue which protects our joints and bones from rubbing of one another

5 types of bones:

long, short, flat, irregular, and sesamoid bones

taking care of our skeleton:

1. wearing a helmet when cycling protects your skull

2. eating a healthy diet helps your bones grow strong

3. being active and exercising helps to strengthen your bones and joints

Life processes

MRS GREN - Movement, respiration, sensitivity, growth, reproduction, excretion, nutrition

movement

all living things move.

• animals move around to get from place to place

• plants grow and turn towards the light

• plants roots move downwards to reach for water

respiration

all living things release energy from their food by respiration. most organisms need oxygen to do this.

sensitivity

Every living thing can detect changes in their surroundings

growth

animals grow from babies to adults. seeds grow into plants. seeds-seedlings-adult plant

life processes - reproduction

animals have young (lay eggs or give birth). plants produce seeds from which more plants grow.

excretion

both plants and animals have to get rid of excess gas and water.

life processes - nutrition

animals/humans eat food in order to get nutrients. plants produce their own food by turning sunlight into energy. this is called photosynthesis.

animals excrete:

• water in the form of urine

• food in a form of stool, or feces

• sweat from skin

• carbon dioxide from breathing out

• burping and farting “release excess gas”

plants excrete:

• plants get rid of CO2 in the air

• plants leaves fall

cell

the unit of a living organism, contains parts to carry out life processes

tissue

group of cells of one type

organ

group of different tissues working together to carry out a job

organ system

group of different organs working together to carry out a job

What is bone marrow?

Spongy or cancellous bones

bone marrow - This bone tissue is filled with…

blood vessels and red and yellow bone marrow.

The red bone marrow inside bones produces…

red blood cells(carry O2), white blood cells ”fight infection” and platelets “blood clotting”

Muscular System functions:

movement, give shape, protect and keep abdominal organs, circulate blood, generate body heat

types of muscles

skeletal, cardiac, smooth

Cardiac Muscle

• heart

• Involuntary muscle(cant control)

Skeletal Muscle

• any muscle attached to bones

• Voluntary muscle “consciously”

Smooth Muscle

• intestines, stomach, bladder

• Involuntary muscle(cant control)

Tendon

A Tendon is a muscle fiber that connects muscles to bones. It ends with a strong, white, flexible cord.

How do muscles work together?

Antagonistic muscles

• muscles cant push, they can only pull on bones.

• a pair of muscles that work together are called Antagonistic muscles. one muscle contracts, the other muscle relaxes.

What happens as we exercise?

• increase blood flow, muscles take more O2 from blood, muscles contract more

• Waste products such as CO2 and Lactic Acid build up in the muscles. These waste products lead to tiredness and cramps.

• Overuse of muscles leads to soreness and strains.

Health Issues Involving the Musculoskeletal System

• Rickets: lack of Vitamin D, calcium, or phosphate

• Arthritis: joints become inflamed and swollen

• Osteoporosis: bone tissue becomes brittle, thin,

  and spongy

how air travels? “breathing”

1. air into mouth or nose

2. trachea

3. bronchus

4. bronchioles

5. alveoli

6. blood vessels

7. body organs

8. you breathe out in the reverse order that the air came in

alveoli “air sacs”

• end of each bronchiole

• this is where exchange of gases take place

• O2 to blood vessels

• CO2 from blood vessels to the lungs, then removed from the body

diaphragm

• main muscle used for breathing

• breathe in (inhale), diaphragm moves down

• breathe out (exhale), diaphragm moves up

• this muscle separates the chest cavity from the abdominal cavity. “abdomin”

main process in the respiratory system is:

breathing and gaseous exchange

inhalation

ribs: move upward and outwards

lungs: are inflated “filled with air”

chest: gets bigger

diaphragm: moves downwards

exhalation

ribs: move downwards and inwards

lungs: are deflated “emptied from air”

chest: gets smaller

diaphragm: moves upward

breathing rate

the number of times we breathe in and out in one minute (about 16 times per min.)

what do we need to calculate breathing rate

stopwatch

how did exercise affect your breathing rate?

Exercise made breathing rate increase. You need more O2 when exercising, so you breathe more often to get more O2 into the body.

bpm=

breaths per minute