7th Grade Rockin Review
In this Tackk we will review the cells in the human body, how our body's systems interact with each other, Heredity & evolution,and more to come.
Brain Cells in Use
Cell- the smallest structural and functional unit of an organism
The difference in animal and plant cells is Cell wall is Absent in a animal. Animal cells are a round shape wile plant cells are rectangular. Only plant cells have chloroplasts because they make their own food.
Muscle Cells- Contain protein filaments of actin and myosin that slide past one another, producing a contraction that changes both the length and the shape of the cell. Muscles function to produce force and motion.
Red Blood Cells- Blood has three main functions: transportation, regulation and protection.
Secretory Cells- Cells that releases chemicals such as salivary cells which release saliva.
An organ is made of several types of tissue and therefore several types of cells. For example, the heart contains muscle tissue that contracts to pump blood, fibrous tissue that makes up the heart valves, and special cells that maintain the rate and rhythm of heartbeats.
The digestive, circulatory, and respiratory systems in our body all work together. In the digestive system our teeth, saliva, stomach, stomach acid, and intestines are all key components in the system that processes food for the body. The teeth crush the food and saliva assists the breakdown of food and helps send it down the esophagus and into the stomach. In the stomach the food is further broken down by acid and then the muscles in your stomach churn the food. The food the is sent to the small intestine so that the villi can take in the nutrient. The nutrient enters the blood stream and the circulatory system. Blood fallows a path thought the right atrium and ventricle and get sent to the lungs to get oxidized and sent back to the hart to get pumped though your body again. When we breath in oxygen goes though the trachea and down in to bronchi. At the end of each bronchi their are alveoli capillaries. In the alveoli capillaries oxygen is defused in to red blood cells and travels throughout the body in the circulatory system. When the red blood cells come back around with carbon dioxide, the carbon dioxide then diffuses into the alveoli and out of the body with the next exhalation. That is the respirator system.
Paramecium lives like other organizes. Parameciums are like plants because their food vacoules of a paramecium act like chloroplasts to use certain elements and convert them into energy for the organism. The oral groove of a paramecium is similar to an animal's mouth as the oral groove takes in the food substance and moves it further into the paramecium.
Form the punnet square below we can see that the two genotypes are Gg. That's one dominant and one recessive. The punnet square predicts 25% GG offspring, 50% Gg offspring, and 25% gg offspring. If the G=green flower and the g= yellow then since the dominant gene in both genotypes is Green the flower will have a 75% chance of being Green and a 25% chance of being yellow. You could also translate the punnet square to have 2 homozygous outcomes (GG and gg) and two heterozygous outcomes (Both Gg so technically just one). With this punnet square we can also see that their are 3 different possible outcomes for the offspring being GG, Gg, or gg.
offspring that result from sexual reproduction are likely to have more diverse characteristics than offspring that result from asexual reproduction, because their parents genotypes are different and in asexual reproduction only one genotype is involved and will eventually it will get to the point when the genotype is GG and reproduces itself with another GG so it will not have any new phenotype possibilities.
Adaptation- a change or the process of change by which an organism or species becomes better suited to its environment.
Evolution- the process by which different kinds of living organisms are thought to have developed and diversified from earlier forms during the history of the earth.
Species- a group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding. The species is the principal natural taxonomic unit, ranking below a genus and denoted by a Latin binomial, e.g., Homo sapiens.
Gene- a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring."proteins coded directly by genes"
Genetic- of or relating to genes or heredity.
Sexual reproduction- the production of new living organisms by combining genetic information from two individuals of different genders.
Asexual reproduction- a mode of reproduction by which offspring arise from a single organism, and inherit the genes of that parent only
Genetic variation is important in breeding because then millions of options are available for an offspring. In animals the ones that survive have the traits that are necessary for survival so they pass on their genes to their offspring. This is how evolving works. the ones who die prove to be inferior to the rest and so their traits die with them.
1. Tropical Rain Forest
-Precipitation - 250cm/yearLittle temp.
-Contains more species than other biomes.
-Open, widely spaced trees, seasonal rainfall
-Parts of Africa, South America & Australia
-Dry, sparce vegetation; scattered grasses
-Parts of Africa, Asia, Australia, North America4.Temperate Grasslands
-Precipitation: 10-60cm/year-Rich soil; tall dense grasses
-Central North America; Central Asia
-25cm/year-Open; wind swept; dry; ground always frozen
-Far northern Asia; Northern North America
decomposer are organisms that break down organic materials. Consumer are organisms thats that eat plants. A ecosystem is a community of living organisms in a particular area and its nonliving environment. A producer is a organism such as a plant that makes it's own food. A food chain is a chart that shows how eats who in ecosystems. Biotic means someing is a Living factor. A abiotic is a Non-biological factor. Adaptation means making
physical changes to live in the environment better.